Nice work!
My experience with these "all in one" wood filler are the same, good for small dings and dents. But if you have to fill a bigger damage, they new "bondo" is drying out maybe too quickly and you will get crack?s again. So you have to redo that 3-4x until its nice.
So I went the path like the other guys and bought a 2 component body filler ( bondo + hardener ) and the hardest part here is to just fill it the right size - otherwise you will spend some time sanding again

But looking at your pictures again, the "one fill" says up to 10 cm and it looks rly nice. It looks like thats a better product than I have bought.
And the metal parts are looking great again, btw that coin insertion looks unknown to me, maybe some italian one?