my suggestions are the following;
US CLASSES (Edits and new classes)
Soldier: good but needs something else? maybe a M4A1 or ACR instead of G36C.
Sniper: good class, good weapon choice. I do believe this could use a VIP Bump of it with a barret.
Explosives specialists: Proxmines and c4 would do better. or maybe the MATADOR. also maybe an smg?
Marksman: M16 ACOG, it would make spence
Support: M60 or Ares

RUSSIA CLASSES (Edits and new classes)
Soldier: Bizon (PP-Bizon)
Sniper: SVD and maybe a VIP class with the Dragonov SVU
Explosives spec: Same idea, but with RPG
Marksman: SVT
Support: PKM with 125 health for balance

These are my suggestions. this does not mean they need to be implomented.