I would like to see more healing options in the game because you seem very limited to a max of 150hp, and as a lone traitor this can be pretty difficult to kill large amounts of enemies. A cool lifesteal option that awards you a little amount of health per kill would be nice and its effectiveness should be reduced when you're in heavy as it could be pretty overpowered
Detectives seem a little limited in their ability to find traitors and keep them, a footprint system that leads them towards the traitor for a short while would look visual cool and add to the sort of detective footprint stereotype.
Innos seem very defenceless against heavy so a cool feature would be a armour penetrating gun that does extra damage to armour that is cheaper for Ds but also purchasable by innos. Talking about heavy, it would be cool if they had a canister on the back which if shot does extra damage.
Some of my recommendations may be a little overpowered but I think they're fun ideas