Although more of the same will still be great, here are some thoughts on ways to differentiate the players and add to the social deduction aspects:
1. Would be great to replace the text chat with real chat. I.e. you can only hear someone when you are in their vicinity.
2. As much as I love the cute little hazmat suits and the cute aesthetic, I wonder how the game might work if you took the hazmat suits off so you could see customisable faces and made the graphics more serious and scary. The hazmats could still be an option. Too drastic maybe?
3. I like Giatorro’s skills idea. A mechanic would find engineer mini tasks easier and fix sabotage quicker, biologist would find biology tasks easier and have a movement sensor, security can seal doors, comms can talk to all players, some characters can move faster than others. Imposters could have abilities like invisibility, walking through walls, shape-shifting (mmm, possibly a step too far). As long as none of this compromises the already great gameplay.