Honestly, I think you really need to post detail pictures, especially of the wear spots on the playfield and of the home made plastic you mentioned. Mentioning those two things probably has people nervous without knowing exactly what they look like. Looking close at the pics in your marketplace ad, it would almost look like a decent size wear spot right down to the wood in the area you mentioned (the martian's right (left from our perspective) upper eyelid?)...but then again that could be reflection or how the art looks there, I'm not sure. Hard to tell with those pics. So I would highly suggest getting some detail pics to help people see the real extent of things.
It's great to disclose issues as you did, but without the pics to detail them, it is easy to assume the worst. When I imagine what a RFM looks like with playfield damage front and center on the martian, a homemade plastic, and without RFM cab art, honestly $2200 seems a bit optimistic. But what is in my mind might be way worse than actuality, so you need to show that.
Hopefully I'm making sense...just trying to help either way. Best of luck with the sale!