If you want to make enemies, try to change something.
30 in mag and 10/15 burst? :] 30 is standard ammo cap. for most of guns.
and the p90 does more damage, at least in my experience. I found the real weapon, it says it uses 5.56mm bullets. What if you change the ammo from 5mm to .233, I think it could be a lot better, like a sniper rifle, less powerful but with burst option.
I think 5mm (as 5.56mm nowadays in real)