IMHO you are splitting hairs, but for good reason. This guitar is probably going to cost more money than I can comprehend so you want it to be perfect.
Basically Spruce feels tighter than cedar. Cedar is warmer but, as you put, you can overplay it and it gets bogged down in mushiness.
Back and side wood makes less difference than the top wood. In my experience mahogony is pretty well balanced and the rosewoods sound a bit warmer. The difference here is pretty small. I have a spruce/rosewood guitar and a cedar/rosewood guitar and my wife (who is a musician but not a guitarist) says she can't tell the difference, and the top wood makes much more difference than the back and sides.
I recommend you see if you can have a go with some guitars that are a similar shape to what you want with different woods and see which you like the best. To be honest, you'll probably be happy whichever wood you decide
If it was me, I'd go for cedar (for the fingerstyle) plus Indian rosewood back and sides. Some people swear by Brazilian but the difference between it and Indian is very (very) small sound wise. The real difference is in the price tag. I'm not completly sure but I suspect Brazillian rosewood would at least double the price of a guitar compared with Indian rosewood. I do admit, Brazilian rosewood looks a lot better.