I still have trouble if I try to join someone who is in a match. We have to meet in a lobby to play together, but that has worked fine for me. It has similar problem that CoD faced, camping snipers on top of EVERY rooftop you can get to.
SOmetimes the vehicle seem to be a bit much, but thats ONLY if your team refuses to help destroy them (heavy tank with monkey wrench ugh!).
The deaths feel cheap sometimes. Like you had no shot even though you may or may not have had a chance at the guy. I've chased people and gotten hit markers several times just to have them swing around and drop me in one fell movement.
Airstrikes on infantry maps get tireing, even though they cost a lot of BP you do see a ton of them. Cold blooded should help that, just having the perk out there makes less people use the airstrikes.
There are others but these are the ones that come to mind for me.