In my opinion the frame looks like it needs a complete good sanding. You should end up with smooth bare metal with small grey looking dots. Re prime and do it all again until the surface is very smooth. (nothing courser than 220 240grit) It's not s good thing to put primer over non sanded primer. The longer you can leave the primer on before painting the smoother the final sand (600 or finer) will be. Auto primer takes about 14 days to cure.
Big pits I think a 2 stage finishing putty would be best. I think those could come out with repeated prime and sand. Prep is 90% of getting a nice paint job. Shops can't wait so they do the color sand a polish.