Thank you for the feedback! We did include in the How To Play that characters open doors of their color but perhaps we should have colored the border around each player to further match the door they opened.
As far as "additional abilities" we actually had planned for each one to have extra abilities! Smuggler had a decoy, scientist had a stasis field, marine had an AK and engineer had a "monster tracker". However due to scope we ended up changing the plan and had to instead give all of them weapons and just made the marine's auto-fire weaker since no one could stop the monster fully anymore.
Also the "smuggler" (since she had no doors she could open) could unlock crates that provided resources for each classes' tools (ammo, batteries and stasis fluid) but since the abilities were scrapped, so was the smuggler's extra ability.
In the grand scheme we just didn't have enough time :) but we are happy you enjoyed what we could get in!