For a 90g tank, what you've posted for potential stock is certainly not too many fish, in my opinion, given the size of the fish you're interested in. If you're going to stock mostly these nano fish (bristlenose, excepted), you could certainly up the numbers you're looking at or look at additional species to include - and there are lots of options.
I love small fish (Habrosus are a favorite of mine) but I keep smaller tanks. If I were looking at a 90g, I think I'd go with some larger specimens - larger tetras or even some of the barbs. But maybe that's just because I've been looking at mostly smaller fish for so long. The largest I have are diamond tetras and Candy Cane tetras in a 40B. A large tank filled with nano sized fish could certainly be an interesting tank.