Pointman - Bizon. Trust me, it's awesome. Almost no recoil as long as you don't run and spray.
Assault - Sako/L85A2. Sako has good damage and L85A2 has literally no recoil.
Sniper - M24. No point of spending 50k just to get a sniper when the deafult is awesome anyway. You just need to hit either head or shoulders and up.