Metal doors: Short of blowing these up or ramming them with a vehicle, the only way method I know of opening these things is by using an acetylene torch + welding goggles to cut them open. If you’re VERY strong I think it’s possible to break the doors down with a sledgehammer.
Wild animals: I believe these respawn even with static spawn on.
Freezing Labs: Yes, there are non-freezing labs.
Sound attracting enemies: I have no clue how this works in static spawn, sorry.
All vehicles being broken: Pretty sure this is a feature, I might be wrong but if I remember correctly according to the lore all the vehicles are broken because all the functioning vehicles have been driven out of the game area by previous survivors. However, it’s possible to find completely functional vehicles abandoned along roads (usually outside of towns) that only need to be refueled to work.
Pawn shop basements: I have no clue. Sorry I can’t help you with this one. However, I didn’t even know pawn shops had basements until now… thanks Malakhaj!
Repeating last action: I don’t think there is.
Anyways, I tried with these answers. Have fun surviving 