I have a similar situation with my boat, I suspect the previous owner had the boat compounded too frequently. For us the hull is fine but some spots on the superstructure are wearing thin, I am sure that we spend 2/3 of our time in FL contributes to the problem. I have found that waxing with 3M cleaner wax a few times a year keeps the hull looking good but the superstructure needs to be waxed more frequently. The 3M cleaner wax has a modest fine grit rubbing compound in it and so I dont want to use it monthly on the superstructure. I have found the the Pro Polish has no compound in it and can be used much more frequently without wearing any more gel coat off. It is the only polish or cleaner wax that I have found that has no grit or compound in it. But if dirt gets embedded into the gel coat, you still need to use the cleaner wax a few times a year to fully clean the pores in the gel coat. If a particular stain is hard to get out, I use the gentlest compound possible, like a color/gloss restorer.