Well you can certainly get Pro Tools HD system for well under $60K. 16 channels of I/O Pro Tools HD native (card or thunderbolt) is about $7K.
I am having difficulty understanding what it is you need 11 R to do and why you need to connect more than one and have Pro Tools see it.
If you need more I/O, there are a ton of interfaces that can give you that AND also interface with 11R.
Regular old Pro Tools can handle up to 32 tracks of simultaneous recording...depending upon your interface.
If you want to record with multiple amps, well the best way to do that is to record ONE patch, the RE-AMP with another patch, keeping both. OR use the Eleven Plug in on the dry track. I do both quite often.
I do have two 11Racks. When I need to record two guitars at the same time, I can simply run BOTH 11R through my interface, which is 18 inputs. If I had 8 11 racks I could record all of them at once and use 8 of the inputs for mono or if I wanted to record stereo, I'd use 16 or them. No problem.
Kemper or Fractal, makes no difference Pro Tools will only let you use one of them at a time as the main interface, just as the 11R.
Just a little FYI here. I mean you gotta do what feels best.