Polishing compound isn't aggressive enough for the degree of damage you have there. I would suggest that you use a more aggressive diminishing rubbing compound such as Meguiar's Ultimate Compound (not Ultimate Polish). That will probably clean it up quite a bit. If that doesn't get you far enough you might want to try using some ultrafine wet sandpaper (followed by rubbing compound and polish), though look up on YouTube how to go about that since misuse could definitely damage the paint irreparably. After doing that you'll need to deal with the rust spots before touching up. Perhaps somebody else will chime in on the best way. There are a number of rust neutralizers on the market and a lot of folks recommend oxalic acid.