For a machine which is 35 year old and apart from a few areas you are concerned about, the PF looks quite good. From previous experience I would leave the mylar on. Chances are removing it will take further paint off.
PM sent (Re: target decals)
+1
That mylar or contact has a really nice shine. It is not lifting. I would leave it intact as removing it presents risks of paint lifting. I would consider using the Treasurecove polishing kit - but a simple clean with Novus 2 and then paste wax will do the trick for this game.
That's a really nice playfield.