I would say that from the perspective of their inner consistency 1935 is way more embarrassing than 1914. It already makes the "exception" more frequent than the "rule" in the current GB membership.
The (quietly forgotten) doctrine of the 7,000-year "creative day" rested on the apparent coincidence of 1975 as the end of 6,000 years and a strict interpretation of the 1914 generation, which has already been discarded out of necessity (plus, the implicit assumption that Jehovah is fond of round figures). Even if they modified the chronology (to have the "day" end somewhere in the 21st century, for instance), it would never work nearly as well as it did in the 60's.
Whatever the rationale, 1914 is globally a good argument for JWs. In the average JW (or prospective convert) mind, it is simplified to "the Watchtower could tell the date of World War I 40 years in advance, and this date-event is the sign of a 'spiritual' change of era". Pseudo-historical as it is, it still works as a "sign" that the Watchtower is God's organisation for the present time.
Christianity as a whole was perfectly able to survive its early short-term expectations through reinterpretation. They are still in the NT but no one really cares. If the Watchtower keeps on providing an otherwise attractive offer on the future religious market (that is the question), I really don't see why 1914 should be a problem.