Those in medical bay or confined to quarters don't count towards parity unless and until they get out. So, they have to be taken out long enough to reach parity.
Bad guys need to cause some sabotage first as distraction before they can attack (disable) anyone. Sabotage can be repaired so it's a balance. Locations can be guarded. People can be defended.
Good guys win when they've caught and identified all the baddies.
Oh, and there's a deck plan.
