Verified answer

Medic: MG36

Assault:AN94

Recon:M95/GOL

Engineer:M2carl

don't spam use M2carl unless you are using it for tanks, you wouldn't want everyone to use it. If everyone's using M2carl except for you its like you using a pistol to fight a chopper.

Hmm well it depends on what game type you are playing.

Assault with the G3 + c4 + extra c4 ammo is good for rush when attacking.

Engineer with mines + extra mines is also good for rush when attacking.

Engineer with the tagger + rocket (not the M4) with extra rockets, (perfect for attacking vehicles and snipers, the tags don't drop with gravity so if you can tag snipers in the face, lock on with the rocket and give them the ultimate tea bagging)

Recon with shotgun, very good for close quarters, make sure an use motion sensors and have a buddy to rearm you.

Medic with the M60 with magnum ammo is unstoppable.

For vehicles consider bringing smoke as it disables tags.