-Balanced all of the guns so each class' guns are almost identical
-Absence of prone to promote fast-paced gameplay
-Vehicles being secondary to infantry
-32 player max
-Absence of jets
-Low helicopter ceiling
-Ridiculous anti-tipping measures for all vehicles
Another thing I hate is that the maps are so "tunneled" so to speak. BC2 was made with a single player. When you make a single player game, you generally tack on a multiplayer. Instead of working on one from the ground up. Generally single player maps or levels are made in a tunnel way, you can't go off course, they funnel you into what your supposed to do, so there is no point in developing the whole map.
The multiplayer maps are BC2 single player levels, that's why they are so tunnel'ish. In Conquest it's always the same thing. 3 flags & two main bases.
Enemy Main Base > Enemy First Base
Middle Base = ****storm
Friendly First Base < Friendly Main Base
There is next to no room to flank around or to try something other then go into the meatgrinder, and like I said the maps aren't even that big to begin with, maybe if the Conquest maps where the same thing as Rush but with Flags. At least then the maps would be somewhat decent.