I rode my Whyte PRST4 on Thursday. Linkage front fork and virtual pivot point rear. It was the future but must not have sold well enough. I chose to ride it because I wanted to get a Strava KOM title on a climb. I got it! but lost contact with the satellite for a big chunk of the ride so it didn't register
. It doesn't bob if you have the correct pressure in the shocks but does dive under braking. The small bump sensitivity is amazing. I lapped a local red route in the summer in 11min 12 on the PRST4 compared to 11min 31 on my modern bike. Some of that is probably down to the 26"x2.1" tyres with their lower drag.
So my bike of the future might already exist and I have 2 of them (a JW4, as well). I would like a 150mm travel front and rear version and may be ready to accept a carbon fibre frame, wheels etc.
CVT is a good idea but tends to absorb 25% of the power on a scooter/moped so it might not work. Putting the transmission at the bottom bracket is the way to go. An epicyclic bottom bracket?
I think I'd go for a 29" wheelset, but keep the width down.