well, there are a shitload of ents that will break because of that.
some maps won't even fire up in any other mode but 4 and 8, part of the 3.5 requirements.
the maps can be made to be cross-mod compatable, but that's pretty damn tough to do if the mapper doesn't know how. if you want a map to exist in more then one gametype, tell the mappers now before the next batch comes out.
btw, we are working on oneflag, regardless of what static says.