I'm not sure what your interest (if any!) is vis-vis the views of the general British population to the dissemination of news from Germany pre-war, but it's an interesting subject area.
Today we have the benefit of hindsight - we have a clearer idea of what was happening and what was going to happen. The treatment of the Jews was atrocious and we must not forget that.
Those reading their newspapers during the 1930s did not have availability of multiple news channels and 24-hour news. They were also fitting what they were being told into a different knowledge background than we have today (for example the reporting of The Rape of Belgium 20 years previous) and they had their own expectations and hopes - this was, in Britain, generally an era of 'appeasement' (and in the US, an era of 'isolationism'). I believe it is important to historically contextualise what was being reported at that time - though we must not minimize in anyway what happened, or excuse it.
Looking back, the Letters published in the Manchester Guardian from Monday 23 April 1945 are interesting:
"... The fact that this has been practised on so large and scientific a scale may startle the more empirically minded. But it will not have surprised those who choose to recall the cruelties of the last-war German and the bestialities which marked the early Nazi years. Sceptics {surely by now a dwindling sect), and others, will perhaps recollect today the enlightened part played by the Manchester Guardian in the pre-war years in acquainting the thinking world with the facts of the concentration camp regime. Your then Berlin correspondent's timely dispatches are now proved beyond all doubt to have been tragically sober and well-informed accounts, and not unpalatable exaggerations to be quickly read and conveniently forgotten... " - B Melland, 20 April 1945
"Now that we have irrefutable proof of the atrocities that have been perpetrated in the Nazi concentration camps, it is interesting, and instructive, to recall the attitude of much of the press (not the Manchester Guardian), of many Conservative MPs, and of a good section of the deluded public in the early days of the Nazi regime towards the accounts of atrocities which did filter through. Such accounts were dismissed as mere propaganda put forward by Socialists or Jews, or, alternatively, if the atrocities were admitted - well, it was only those 'wicked Socialists' or those 'despicable Jews' who were being ill-treated. Perhaps the democratic peoples have now learned that a nation or a Government that can perpetrate such atrocities against any of its people is a danger to the whole human race." - E Hough, 19 April 1945
And regarding the British public's belief and view of the stories about Nazi atrocities, even towards the end of the war? In December 1944 37% believed them to be true - with 29% believing them to be 'partly true', 11% thinking them 'false', and (I think an amazingly high) 23% of the British public having 'no opinion' about them. BUT a few months later in April 1945 that had changed. Then 81% believed them to be 'true', 16% as 'partly true', 3% as 'false' and 0% as having 'no opinion'. One, of a number of 'turning points' for the British public was no doubt the publication of photos that had not been available before that time. Pictures played an important part.
Thank you for the summary list (of just a few) of the newspaper articles you found.
Interestingly, looking through them there was one reference which immediately stood out to me and I therefore looked it up - In contrast to the others it was not a newspaper, it was a mass-market weekly magazine with pictures, and I suspect would have had a longer 'shelf-life' in the house and was even likely to be kept.
Remember, The Guardian had published on 1 January 1934 the following article (with no pictures): DACHAU CONCENTRATION CAMP - Report on its Organisation, Routine, and Recent History - PUNISHMENT AND ILL-TREATMENT OF PRISONERS
https://www.theguardian.com/theguardian/from-the-archive-blog/2011/may/25/guardian190-dachau-1934
This was followed five weeks later, as you highlighted, by the following double page spread, with eight (rather innocuous) pictures:
Illustrated London News, 10th February 1934: Camps for political prisoners under the Nazi regime

Hitherto little has been available by way of illustration of the German concentration camps for political prisoners under the Nazi regime, about which there has been so much rumour and discussion. Unique interest consequently belongs to these photographs, lately to hand from a French source, and secured, it is stated, on the first occasion on which a journalist has been authorised to take pictures in the camp at Dachau.
Although as far back as last October a message from Berlin stated that the camps were to be abolished, and that "most of them had already been closed down," recent news does not fulfil that prophecy. On January 26 Herr Gerhardt Seger, former secretary of the German Peace Society, was reported to have said that there were still sixty concentration camps in Germany, containing 50,000 political prisoners. Meanwhile, however, there seems to be no doubt that large numbers of prisoners have been released from time to time, partly in view of the Nazi electoral triumph, and also as a gesture of goodwill at Christmas, preference being given to prisoners of good behaviour and especially to fathers of large families. Those released were urged to enter the Nazi fold, and at the same time were warned that any relapse on their part into hostility towards the Government would meet with "rigorous, unrelenting, and final measures."
A recent sidelight on the question was thrown by the case of three Roman Catholic priests, arrested last November, who were sentenced on January 24, at Munich, to several months' imprisonment. One of the priests was accused of having fabricated stories of atrocities said to have been committed in the camp at Dachau, and the others of having passed on these stories.
It may be recalled also that, some few months ago, attention was drawn, by Major General Sir Neill Malcolm, to alleged ill-treatment of a well-known prisoner, Herr Ebert, son of the first President of the German Republic, "to whom (said General Malcolm) Germans owe far more than many of them are now willing to admit." In a letter to The Times, all the more impressive from its sympathetic tone towards Nazi rule, General Malcolm made the following statements (here somewhat abridged): "I am not one of those who can see no virtue in the Hitler regime. To me it seems that his Government, like most other Governments, has done much that is good. It has certainly restored to a great majority of Germans that feeling of national self-respect which is perhaps the most precious possession of a great people. Nevertheless, in common with other revolutionary movements, the Hitler regime has an unpleasant side, which is doing Germany much harm in the eyes of the outside world. I believe that there are very many right-minded Germans who know little or nothing of the administration of the concentration camps. I believe there are others who do know and heartily disapprove." Some three weeks later General Malcolm made known, "without comment," an account of a visit to Herr Ebert, at the Borgemoor camp, by a member of the Prussian Ministry of the Interior, to whom Ebert said he had experienced no ill-treatment. At the same time it was reported from Berlin that, while no denial of General Malcolm's statements, or reference to them, had apparently been published in Germany. Herr Ebert had suddenly appeared at another camp, at Lichtenburg, where he was seen, looking physically fit and well-fed, by a group of foreign visitors including a British journalist.
The correspondent from whom the above photographs came, describing his visit to Dachau, writes: "To this camp the Hitler Government has sent its most formidable opponents. Dachau is a little village on a hill thirty kilometres from Munich. The motor-bus from the station is always full, for the camp commandant allows the prisoners' parents to bring them, from time to time, food, linen, and tobacco. All about the camp were guards in green uniform, armed to the teeth, and from a turret in a corner two machine - guns point towards the gate. 'There are here,' said the Commandant, '2500 prisoners and 400 guards. That is why our men are armed and we have barbed wire charged with electricity. So far we have set free, provisionally, nearly 600 prisoners, of whom only about 50 have returned.' The prisoners were ordered to build a memorial to Horst Wessel, and adorn their barrack walls with portraits of Hitler, and the swastika sign, which appears on workshop walls, worktables, and even tools. The organisation of the camp is excellent, and when inspecting the dormitories, the living quarters, the kitchens, and the hospital, one recalls that meticulous organisation is the chief virtue of the Germans. The workshops are provided with modern machinery, and Dachau is, in effect, a highly up-to-date 'factory.'"
(note paragraph breaks added)
I think even articles written 20 years ago need to be historically contextualised within what was known and/or accepted at the time. Thankfully there has been a growing worldwide acknowledgement, in particular, since the 1990s that we must learn more and never forget what happened as more museums and memorials are established.
For example the United States official Holocaust Memorial Museum (ushmm.org) in Washington was dedicated in 1993, and in Britain, The National Holocaust Centre and Museum (nationalholocaustcentre.net) opened in 1995. The recognition of Holocaust Remembrance Day/s in many countries has come much more into being from the 1990s, with the UN, in 2005, designating 27 January as International Holocaust Remembrance Day.
In addition, the relatively recent advent of technology, with for example the digitization of newspapers, is now enabling much research to be untaken in a more easier and comprehensive way. It is specifically due to those recent advances, that it is really only now that the United States Holocaust Memorial Museum can undertake to mount an exhibition such as the forthcoming 2018 History Unfolded: U.S. Newspapers and the Holocaust that I've previously mentioned in this thread. It will be interesting to keep an eye out for this.
https://newspapers.ushmm.org/
Sorry for going somewhat off-topic - in conclusion: Does anyone know of any books or studies that have been done regarding the news reporting in Britain during the 1930s??
There appears to be a fair amount regarding reporting during and after the war - for example the PhD thesis below, but not really before (or the inter-war period)
Belsen, Dachau, 1945: Newspapers and the First Draft of History
Sarah Coates BA (Hons.) - Thesis - Doctor of Philosophy, Deakin University, March 2016
This thesis examines how Nazi concentration camps were first presented to the British and American general public. It focuses on the nature of press coverage in 1945, identifying themes that emerged in British and American newspaper reportage of two Nazi concentration camps, Belsen and Dachau, in the immediate aftermath of liberation and during the subsequent trials of camp personnel. In examining the two historically critical events of liberation and military trials and focusing on two major Nazi camps, this thesis grapples with the links between early reporting and ongoing misunderstandings about the concentration camp system. Recognising the pivotal role journalists play in forming the 'first rough draft' of concentration camp history, it is argued that the way liberation is remembered today and what concentration camps are seen to represent is linked closely to the contemporary framing of camps. The thesis identifies how the press portrayed key themes in the camps and structured these to create, in some cases, a highly problematic discourse reflective of the values of correspondents and photographers, the conventions of the time, and national ideals and desires.
http://dro.deakin.edu.au/eserv/DU:30088987/coates-belsendachau-2016A.pdf
https://blogs.deakin.edu.au/contemporary-history-studies/sarah-coates