His combat roll is hands down the worst ability in the game. It’s a “quick-reload” and faux-mobility maneuver that mostly just causes him to be vulnerable for several frames. Nothing like dying with a fully loaded gun.
Ironically(?) his best function currently is in the “Anti-Tank” role, being able to reliably drop over 500 damage (perfect hits: 270, 25(stun), 270). Stun + Headshot also eliminates unprotected Tracer (25 + 140). A majority of targets reliably die with 2 headshots.
I would propose to get rid of combat roll for a self-buff: Bourbon shot: damage resistance improves greatly (~60%) for 3-4s. Reliably using this before doing a riskier Dead-eye or as a means of supporting survival would be far more useful to his current kit.