Fall of Berlin is an awful map: It used to be my favorite, but people have gotten it figured out to the point that the PAC side, if they're the worse team, will pretty much get trapped in their spawn area and shat on all game. It's one thing to have a bad team. I can tolerate that simply by avoiding them, and fighting on the fringe of their zergish idiocy. On Fall of Berlin, this is impossible. There's literally nowhere you can go that isn't getting spammed by grenades, by APC mortar fire, by a walker, by small arms. You can't escape your own spawn. It's ridiculous. Fix the PAC spawn area by opening it up and adding some other ways out.
APM mines continue to ruin the game: These things are so overpowered, and so easy to use, that people have gotten to the point that they'll just run up to enemies and chuck down a mine. Doesn't matter if they die, the mine will arm, the enemy will get blown up. People just toss them all around and get kills without any planning at all. Reduce their range. If their owner is dead and they're not armed yet, they should vanish. If their owner is dead for more than 10 seconds, they should vanish.
Anti-vehicle mines also ruin the game: Not as bad as anti-personnel mines, but bad. They will actually pursue a vehicle and blow it up, generally faster than the vehicle can move. Either reduce their detection range, or make them slower. We don't need to include mines in the game to make no talent hacks feel involved. Let them figure out they blow, and go play something else.
Artillery ruins the game: This was true in BF2, and it's true again in BF2142. It's not totally horrible, I understand that DICE wanted to have something for the commander to do, but it's just annoying. It's not hard to EMP strike a walker, then hit it with artillery. It's not hard to scan the field and spam artillery at the biggest cluster of red dots. It's not hard to see a flag go neutral and spam artillery at it. In the meantime, artillery throws up all sorts of dust and dirt, and makes shooting impossible, even if you're not near it. In this respect, even your own artillery is extremely annoying, as it often blocks your line of sight to the enemies it's trying to hit. This is a first person shooter. If it doesn't involve spotting an enemy and placing accurate fire on target, then it should have a minimal presence in the game. That goes for mines, for artillery, for sentry guns, etc. Sentry guns are fine. They get me from time to time, but they're easily taken out if you're careful. Reduce the duration on artillery strikes, and decrease the recycle rate.
Please, PLEASE don't get in my vehicle: I can't stress this strongly enough. Don't see me jumping into a jeep or tank and beg me to give you a ride. I can both drive a jeep and operate the gun far better than you can just operate the gun. I am infintely sick of driving my jeep up to a cluster of unaware enemy, and then sitting there mashing the F2 button, wishing I could switch to the gun and maul them, while my gunner checks to make sure there aren't an badguys where we just came from. In tanks, the anti-aircraft gun is what I use to kill the squadmates of the guy I just nailed with the main gun. They took away my coaxial machine gun, so now I need the top turret too. When you're up there, doing a little stargazing, I can't use the gun for actual killing relted tasks. I can literally do three things at once better than you can do one. That's why I'm 28-7 and you're 10-14. Go stagger around and give the enemy something to shoot at, so I can flank them. That's what you're there for. Just remove the E key from your keyboard. You won't need it.
The correct unlock sequence: Grenades, Sprintcor, Staminar, Defib, Advanced Med Hub. From there, either finish off and get the Voss (it's a better all around weapon than the Baur), or go for the Rockets. The Baur is worth having for wider open maps (like the ridiculous Fall of Berlin). Assault is the class. All others are situational.