A high-risk, high-reward play I've seen is to kill someone, report the body, and claim you were on security camera and saw someone else do it. You can be caught out if it doesn't make sense for you to have been watching the cams, but while people keep a mental inventory of "who I saw doing what tasks," it often doesn't extend to the security room.
Imho, if you where a teammate and not a imposter, you should be voted out regardless if you're just lurking in security and not doing your tasks, so we can finish the game. But then there might be little incentive for you to do your tasks as ghost anyways. Or you can withhold doing tasks as ghost on purpose just to spite the crewmates that voted you out. Like I said this game has many dimensions, wheel within wheels.
Depends, I've had a game where I was not the imposter but had 3 crewmates voted out on reports I made, yet I was not voted out myself. I would have been really suspicious of someone by that point myself.
