A utility focused deck: Breacher.

The smoke grenade stops being a magic trick to use on yourself, and becomes a map control tool.
Cards that benefits some tasteful weapon choices, like shotguns and pistols.

Grenade would be something like: Lasts 10 seconds, any enemy inside the grenade will not shoot, and enemies will avoid stepping into the cloud. Players get a 2 second speed boost (50-100%) for stepping into the cloud. 60 second cooldown with the usual kill reduction.

Twitch, subtle and agility can stay similar (I'm not sure how to cram in more survivability, i know he'd need it.)

Unseen shadow: While your throwable is on cooldown, you reload 50% faster. Any pistol over 100 damage now pierces body armor and shields.
(idk if it's possible to make any pistol also open doors in a single shot, but that'd fit in really well, theme wise)

I am no balance professional, so this would always be up to experimentation and discussion.
Just a thought.