Really just following normal Hyper-V best practices is enough. If you need Live TV then you’ll need http://www.missingremote.com/dca-bypass as well.
You don’t need 3D virtual graphics for extender usage. The best thing is to have a dedicated “server-grade” (i.e. Intel PCIe) NIC for the host and for the VM.
For a recording drive I had the best results with a dedicated drive as well instead of a VHD.
