I've priced Aphex 188's closer to $1100 per unit. You could do a 48 channel SAC system with 32-40 channels from stage of 188 and another 8-16 for I/O back at the board of something like the Octopre Dynamic and easily be in the $10-14K range. Then you don't have to deal with the 64 channels and repatching things from stage boxes to a new preamp channel followed by reassigning everything within SAC. Big bonus is the remote preamps in that case.
Can you use Dante, and the new focusrite Dante preamps? Having a network I/O system would be a big advantage, and allow for putting I/O where ever you want it.
Mac
It would take a bit more configuring, but I've also looked at Aphex with Appsys ADAT multi-core extenders. There are 64 channel versions that get you whatever you want split out of 64 channels in banks of 8 (32x32, 40x24, 48x16, etc). It runs in two banks of 32 and you can extend either bank of 32 to an alternate location with just another CAT5+ run and a less expensive 32 channel version. You could run 64 channels from stage to FOH, then take 32 outputs and place them next to the amp rack.
The Dante stuff would cost more and likely be much easier to manage, but then you start getting into Brad's conundrum. Would I rather have a SAC rig than a smaller iLive setup or an SC48? The SAC rig is more flexible for mixer configuration and internal routing, but do I really need all that? One thing I'd definitely lose is the dual solo busses and ability to function as multiple consoles rather than a single console with auxes and matrixes tapped from it. Remote mixing options like iPad apps can go some distance toward mitigating that though.
