1) view/tilt behavior is untouchable, no improvements can ever be made
I value stability, especially with regard to levels that rely on specific camera behaviour. Still, I don't think your statement is necessarily true. First, let's distinguish here. After the lockstep change, auto-rotation was too lazy for slow movements and too harsh for fast ones. No reason was given why this constituted an improvement. In fact, no reason at all was given for the change.
With r2931, it's different. I actually don't have any hard feelings about that one; it was a reasonable attempt to address a valid complaint. However, much as I tried to like it, way more force seemed to be necessary now to turn the view while flying, taking the fun out of quite a number of levels. So instead of forcing the change on players (including myself), I decided to implement a preference. With Nuncabola, you get a choice.
If the vertical-exclusion camera is an all-round improvement, then surely I am the one who puts himself at a disadvantage by sticking with the 1.4.0-1.5.1 behaviour. If, on the other hand, it's an improvement only in some situations and detrimental in others, then perhaps it should be configurable in Neverball, too. Whether in the config file only, or through a new entry in the options screen, or as a dedicated camera in the F4 slot, or something else, is open to debate. If I had the ideal solution, I'd have posted about it by now.
2) fair game takes a back seat to Elviz's own convenience.
I'm afraid we don't share the same view of what's "fair". If you believe that the r2931 change should have caused a reset of the Nevertable, with new conditions for uploading and invalidation of existing replays, then you should have said so at the time of the 1.5.2 release. Killing the renascent contest at that stage would have been pretty daft if you ask me, but I'm sure it would have been discussed and some kind of decision reached. However, you didn't say a thing and neither did anyone else.
If anything, I'm doing the right thing by providing an application that lets you compete with every replay on the 1.5 table, old or new. And frankly, in the end general success on the Nevertable depends on entirely different factors.