I prefer the wet sanding by hand too, followed by a good couple of passes with the rotary, then seal with CquartUK ceramic coating.
Recently tried the kits like you and thought they sucked in honesty and a waste of money.
What did you use to seal them and protect them from yellowing up?
I thought my OCD was bad, but nothing compared to yours
How tricky was is it to remove the window surrounds, still not 100% happy with the wrap I’ve done?