Thats funny that you say that, because I felt the exact opposite. The M16 with red dot and suppressor (warlord turned on) is one of the better guns and you get that early.
I have 2 "go to" classes set up.
Commando - Red dot - Supressor
Ghost Pro - Warlord Pro - Ninja Pro
and
Stoner63 - Red dot - Extended Mag
Ghost Pro - Warlord Pro - Ninja Pro