I've encountered this problem in COD and Killzone 3. It looks like it may be in this game too. It's has to due with the fact the game end right after the objective is complete. Let me give an example....
Enemy team is having trouble planting a bomb to advance the bot in container city. The bomb cannot be planted. So the team decides to let them get through to extend the game, because you would progress farther by doing so. I think they should either make it very easy to plant the bomb, or give you bonus XP for completing the objectives early.
Concern #2
I'm concerned light rifles may be underpowered. They seem rather weak. I'm not saying they have to be like snipers, but I think they should knock people back, for the bolt actions at least. And the semi autos have some good damage, moderate recoil and a varying fire rate.
I just hope it isn't like black ops where the assault rifles and SOME of the SMGs dominate everything. And then there is one hybrid assault rifle that just owns all. I want every gun to have varied stats and be balanced, like gun A has high fire rate, high damage and very high recoil, gun B has Excedingly high accuracy but a low RoF and damage, gun C has high damage, high accuracy, but a very low fire rate etc.....