The timing of the helicopter is really problematic. Why does it appear already after ~1-2 minutes and then stay for so long?
You should have the round go on for longer (say, ~3-4) minutes, then have a marker appear where the helicopter will go and a timer counting down to when it'll get there. When it does, it'll only stay for 30 seconds (
max). People should already be there.
I remember port made something like this called Borg.
The only thing I didn't like about it was that you could literally tell who anybody infected was and then you'd die like right away.
I like how this is a more stealthy way of playing infected.
If anything, this is much less stealthy. Everyone gets announcements about who's infected, shape names are on and the infected have very obvious particles and different colors.