Netflix used to have a challenge to create a prediction algorithm for movies people would like. The challenge was that you could never get better than 80-90% because people's choices change all the time - this is interesting and likely true.
If you compare the 14 films I gave my highest rating to with my 'top ten fav movies' in the OP, you'll see that 5 films are in both categories. Those five are: Alien, The Empire Strikes Back, The Thing, The Fly and Silence of the Lambs.
I still like the other 5 films in my OP from 2 years ago - Star Wars A New Hope, Halloween, The Terminator, A Nightmare on Elm Street and Shaun of the Dead - but I don't rate them as highly.
Subjectively speaking, A Nightmare on Elm Street is my fav horror film but objectively speaking - it has a couple of flaws and therefore doesn't get my highest grade and isn't a masterpiece ... but I still love it. I'd give it 9/10.
I expect my list of my highest-rated films to grow in time as I see more and more movies and as I learn more about how stories are/should be told and how films are/should be made.