So I don't see why there's a discussion about amps really. Before you can really start to look at a specific component have you ruled out everything else including speakers? (If so I missed that part of the thread! Apologies!) While keeping in mind everything is relative, I for example bought a used pair of speakers that completely blow my mind every time I listen to something.
So what I'm saying is everyone really needs to have an understanding of where you're at to begin with. Then there can be discussions on what part of the system should be focused on first and then go from there.
If your speakers are say currently in the $1000 dollar value I'd be tempted to throw a good majority of that $7500 at speakers. And like I pointed out if you're willing to go used then you can find some fantastic values out there! I know I did.
I think if you've already got some components I think I'd be likely looking at my speakers first unless they are already worth $7500 or more.
Hope that helps,
E.