The really weapon that need to be buff is Magnus. It is a heavy gun, 2 fast bullet, Movement penalty when charging, and Deal knockbacks to you and enemy when deal charge shot. So why The valiance can push back the enemy in regular shot while Magnus cannot? Valiance is just like a light gun. So, for me, it's doesn't make sense. But, Luckily the Magnus can interrupt beast movement. But it's still missing somewhere.
The solution
> Slightly can push back the enemy a little bit in regular shot
> Deal more damage since it only has 2 bullet.
Magnus line is supposed to be more damage per hit in exchange for mobility. Callahan "nails" the target, dealing pierce and inflicting stun; this is also supposed to do high damage. Adding more damage to it would be fitting.