I think it worth distinguishing between the interface used by the remote and the interface used by the A/V components.

I would strongly suggest against using an activity based remote that uses IR. Commands will be dropped and so control will fail and the system will be put in an unknown state. That leaves RF and IP (via WiFi.)

You can still get away with IR based control on devices, though look for devices that have discrete control.

Of course, since the remote is not IR, you need a control gateway between the remote and the components to achieve this.

Two-way control via serial, IP, etc. are great, but as pointed out is not yet a slam dunk.