Itīs not a complete solution for your problem but the VI host problem should be resolved. check out RAX for $59 sale until 29th.
http://www.audiofile-engineering.com/rax/
there are some ethernet solutions but I have the info not at hand right now.
But you can always us MIDI interfeces and S/PDIF connections as a workaround.
For Reaper there is also ReaMote for remote controlling, But itīs only for clustering Reaper DAWs on different computers as far as I understand it.
So theoretically you can run Reaper on both machines, ReaMote them and ReWire the local one into PT.