I'd remove the 10% damage res and put a -25% fireing and deploy speed

Follows the three hit combo:
On each successful hit: Deal +10% more dmg (Scales up to +40% dmg)
On every successfully timed third hit: deal mini-crit dmg
On kill: Gain +25% faster movement speed for 3 seconds
+15% slower movement speed while active
Deals -20% dmg

To simplify: Gain up to +40% dmg on each hit, every 3rd hit is a mini-crit, and kills give a 3 second movement boost, however, you are slower and start off with less dmg.

Basically a snowball weapon for Heavy.

The Gothic Gauntlets
Level 17th Century Gauntlets

+ 30% more Damage
+ Reload: bring your arms together to block all incoming damage in front of you
+ 10% damage resistance on wearer
- 100% slower switch-from speed.
- 100% slower switch-to speed.
- No random Crits

5% slower walking speed
20% more damage
10% less firing speed
2% damage resistance

oh and lvl 20 boxing gloves

maybe just a iron fist reskin