As a singleplayer, I don’t really have enough information to cast a vote. But I do have a couple of thoughts that I hope may be relevant -
Firstly - I would not want to see any sort of cap (no matter how high and reasonable) placed on singleplayer or private servers - that should be left to players and admins to decide for themselves. (At the very least, such a measure would require a toggle on/off setting.)
Secondly - I’m not convinced a cap would be a good solution for official servers either for the sorts of reasons people have been expressing in this thread:
(In particular, Codemage’s point about the difference between a 201 piece building and a 199 piece building strikes me as getting to the heart of the problem).
Of course, I recognise that you are not calling for a cap, and are just gathering data on what players think is reasonable, but I feel like these points need to be made, since it would be potentially easy (depending on what results you get) for someone to then misinterpret your data as general support for the idea of a cap.