there were some "features" that were worth complaining about, but got you banned for even talking about them
The only one I recall being a bannable offense was complaining about the 20 vehicle limit, which, I tested it with just like 3 players, and having 20 vehicles. It was sending a stuffload of data, going over my "packet size"/"rate to client/server" settings just to try and keep it stable.
I can honestly say that 20 is more than what we should be able to use.
I can't think of anything else, aside from shapename distances having a minimum limit.