Nah.
When it was 120 it was laggy like hell (Ok, that would probably change with a new server) but more than that is just not cool with the current maps. Most maps would probably turn out to be almost uncaptureable with so many players on.
But many of the new (big) maps would probably be not so shitty anymore. Nevertheless, Siege with 200 players would not work on current maps.
Fix the flag-bug, this is much more annoying