My sugestions here:
1-More between impostor and crewmate.
As many commented below, there could be a doctor, as there is a medbay in Among Us. The doctor could not kill anyone, but he could revive someone who died less than 10 seconds ago. If revived, he will not be able to speak during the emergency because he knows the imposter.
Of course, a security guard or a detective. A security guard (or detective) to watch the cameras. He cannot kill crewmates and does not even need to do tasks, he would watch the cameras, investigate the ship and so on, to investigate suspicious activity.
2-Friend list
Please, an friend list. I want to send friend requests to the people in the servers, for we play together.
3-More game options.
Hide and seek, run from impostor, and another themes or even "only talking theme" are so popular in the game, then Innersloth can add another game options. That can help a lot the players.
4-New tasks, new missions.
A few days ago i dreamed i was playing Among Us and i was in a strange room, with medicines, potions and samples that should not be touched, or I would die. I also thought of a room that offered the function of observing the health of a player during the game, as if it were possible to get sick.
It could also be possible to pilot the ship, with the function of "pilot". That would be really fun. And we could also unlock items, pets and skins by completing levels and more.
5-Pets, do something!
Pets could start to warn you when someone died near you, they could guide you to the nearest tasks and more.
6-I am on Polus! But.. but.. WAIT! A ALIEN! AAAAAH
This idea of mine will be a little crazy, but interesting. Since crewmates will have help from doctors, pilots, and detectives, impostors could have help from aliens who would infiltrate astronaut clothing. The alien, as well as the impostor, would infect the innocent in 5-20 seconds (this could be decided in the server configuration, made by the host) and the innocent could be cured only with the help of a doctor.
An alien cannot kill an imposter, just as an imposter cannot kill an alien.
Aliens, imposters and crewmates could wear the same outfit.
Detectives could wear a detective outfit. And they cannot kill anyone.
Doctors could wear a doctor's outfit. And they cannot kill anyone.
Aliens can kill any innocent by using some toxic power that makes the innocent sick, slowing down their speed and vision.
Impostors can kill normally.
In a room of 10 people and 2 imposters, in general:
6 crewmates.
1 detective.
1 doctor.
2 imposters, among them, an alien.