Looking really good there
KadstaBlitz. Ton of work to be proud of there.
PlanetAlexander and I clearly shop the same stores. I'm also a fan of the SCA brand sprays. I tend to alternate between a coat of the Filler Primer, and the Spray Putty. Partly because that makes it alternating coats of thicker and thinner filling, but they are two different shades of gray which makes it nice when sanding to see how deep you're going. I notice Alexander is referencing Australian stores: Are you Australian Regiment as well?
Another filler/smoothing option is
Monocure3d resin paste. And yeah, its not cheap but
its good value. I find its nice to work with and less waste than a Bondo-like body filler. It doesn't dry while you're applying it. Its UV cure just like 3d printer resin, but with a consistency of hair paste. You can apply it, smooth it, use a plastic razor blade to apply it with a scraping motion that only fills the grooves and leaves a flat smooth surface and put the excess putty back in the jar for later, before shining a UV flashlight on it to set it. I find I'm not racing the clock and the drying speed of body filler paste.