What server? Assuming EN
- NZ75 would be pretty good in either 8 or 2 (num-pad position) due to her skill and the evasion buff for makarov, plus a little extra damage for whoever is behind her. Good survivability/damage combo
- If you're looking for more rof, you could do m1911 (survivability/rof) or ppk (pure rof/damage).
Honestly either of the three would probably be equal in survivability, because killing enemies faster than they can hurt you also prevents damage taken, usually more reliably than evasion.
As for the versatile nuke squad, it's not really a *bad* idea. Especially with springfield's special equip, her pre 6-second dps is the best of any rifle (iirc), so it's not impossible to get her to kill most enemies before they fire a shot. However when they release later chapters you're going to want dedicated nuke squads for particular mission.