hi Stefan,
it may well develop into problem down the road, its hard to say. is the thin spot on a brace? i asume it probably is, also around the crack, maybe its puckered slightly?
generally a customer wont realistically expect a virtually destroyed guitar to be 100% again, getting it structurally back as it should be would be my priority, ie braces fixed, reglued etc - to the point where its not going to implode any time soon.
the joys of being a repairman are many and varied eh?
some jobs i take on at a lost just to do em and learn that little bit more, although i sometimes feel i need my head tested!
Try getting some nice small-ish photos (dont make my mistake
) and send them to Frank Ford at frets.com - hallowed by his name - he may well have some better advice