That color with the gold flake should look killer. I like the "to hell with it" paint mixing method, it usually works great. Free paint always looks better to me. As far as the seat goes, if it was "factory" to put a cornbread pan on there for a seat, it was probably because of cost anyway, with style taking the hindmost. Make it comfortable. Speedos were factory, but you can't wear one without looking like an uncomfortable nincompoop.
I have a '69 Karmann Ghia in my shop that has been hit in the left front. My plan is to put Mercedes E320 headlights in it. They are a laid back elliptical shape instead of the squared up sealed beam. Some VW purests will be pissed, but its my car. It looks better to me. The way it should have been in the first place.