My feedback on Arsenal Control set:
For reference, I played an Arsenal/Dark Controller w/ full IO sets.
This set feels really good, especially with /dark. Felt very safe. Pet is a super tank, got it up to soft capped Def and capped Res very easy. It does fell weird having a gun and doing minimal damage, however it is a control set so I wouldn't say that needs to be changed.
Liquid Nitrogen - Feels like a long cool down, would be nicer to have a faster cool down for leveling, but I'm sure it's on par with other ice patch abilities.
Smoke Canister, Flash Bang, & Tear Gas - Really like these abilities!