Body Filler Preferences

I've used just about everything and I've found to take a liking to evercoat Z grip, which is good on bare metal that has been ground/ sanded with 50 grit or coarser.

Rage Gold kind of sucks for sanding, compared to some of the more modern fillers. I've had a lot of pinhole issues with it and it seems to purge a lot of resin after it's dried. It sands well when you let it sit up for semi-dry sanding or cutting with a cheese grater tool, but I don't like it compared to the other Evercoat stuff out there.

Z grip shouldn't be used over paint or primer. You can glaze sanded paint that has been sanded with at least 80 grit, but I wouldn't recommend going finer. Most will go to 180 on paint, but I don't like going finer than 80, before applying filler.

I also use a polyester primer on top of body work that is extensive, to help level the entire area. A lot of it comes off, but it really puts a nice even sand scratch coat on the entire car that doesn't shrink like some 2k primers can and show up in metalics and clears, weeks after. I usually step away from doing filler work at 80 grit, then go straight to poly primer and sand it with 320 linear paper on a 2 foot longboard, dry with a guide coat. Tells you everything. After that, I prime with 2k, let it sit for a week, block sand with guide coat on linear P400 grit, do it again and hit it with 600 wet on a block, with more guide coat. That checks out with some 100k neon tube lights in the booth to tell me if it's straight enough to paint.

That small repair should do fine with an epoxy primer in the small areas, blended base and cleared with blend solvent wherever you choose to stop, if you choose to blend.