Does anyone honestly believe there will ever be a 1.0? :D
A new major release usually includes a compatibility break. We still didn't recover from the last one... And I don't know about any big feature that would justify a compatibility break
Well it includes 3 issues. Map compression isn't really important since the embedded images are the biggest part of the files, bots would be possible without a break and downloadable content is rather useless without a modding system which can actually use the resources.
I think gameplay elements would be enthusiastically welcomed and played with, even if not on ctf5. mods abuse every little resource vanilla teeworlds has
Well ddrace doesn't really use ninja itself :D they just abuse the skin. Sushi once made a really cool race map that uses the fact that you can change direction without losing speed with ninja