As someone who's not flown F on the A380 yet...

I'd probably connect in MIA to a 777 (or A321T) if the times work, but not to any other domestic F aircraft. That flight is too long, and potentially too uncomfortable (with bells on if it involves a redeye) to justify any benefit of the A380 over a 747 or 777.

Even then I'd only be connecting through MIA if I was placing a particular premium on the travel experience.

My personal choice would otherwise be PHX, on the basis that you want the international leg to be as long as possible when not chasing TPs, all other things being equal.