You should really launch it imo, it'll be launched on otw right ? Then let it be here as long as it takes to fix all the other issues, atleast we finally can test it, and you can put a end on this "waiting phenomon" that everyone make fun of.
Fixing the latest issues with apb 2.1 on otw wouldn't bother anyone, we're all aware that it's not the final product, just let it be.
The hype is already too big since 2014, the longer we wait the more people will expect from this engine upgrade, and also the more people might be disappointed if it happens to be bad.
(Even tho I'm aware all that work isn't necessarily done for the current playerbase but also for the future new comers, but yet we will be the first to test it, and we know more about the game than the future players)