Hi mate, thanks for the post!
You're best bet is to begin with a deep clean of the areas that require paint, clay etc to remove as much of the crap out of the existing paintwork as possible. Then you're suggestion sounds perfectly feasible - over fill the damage with excess paint, building it up layer by layer so it hardens right the way through. Then rather than jump straight in with compounding, I would flat the area back using 1500 or 2000 grit paper (wet), refine with 3000grit, so that the effected area is levelled, then do your compounding. To avoid holograms after this phase, use a finishing polish afterwards.
Get some pics up if you try it.