As a person who only uses guns, I've realized exactly how useful the dash (Shift + RMB) can be. So my suggestion is a simple, yet very useful one. I believe there should be a stat called "Dash Cooldown Reduction" which, as the name suggests, reduces the cooldown for your dash ability. It would be added to most gunslinger armor sets as well as maybe the wolver set. I think every tier should reduce the cooldown by 1 second.
Low - 1 second reduction, 7 second cooldown
Medium - 2 second reduction, 6 second cooldown
High - 3 second reduction, 5 second cooldown
Very High - 4 second reduction, 4 second cooldown
Ultra - 5 second reduction, 3 second cooldown
Maximum! - 6 second reduction, 2 second cooldown
So long as this sort of thing is rare (better for bombers and swordies rather than gunslingers tbh) like how MSI is only on 3 sets of gear, then that should be okay.
The highest amount you should be able to get should be "medium" IMO. I don't want to encounter a player in lockdown who is dashing every 2 seconds.