Modern Buddy

Hello fellow scooter fans! Recently on a 2-hour ride, mostly going 30-35mph, my scooter suddenly rapidly lost acceleration. This was a huge surprise as I followed the stock manual's maintenance checklist about 200 miles before that and it was running great. For some reason, it went from ~35mph to ~20mph in about 3 seconds then died entirely after another 3 seconds. Afterward, I restarted it and it would make it up to 25mph almost exactly then would die again. I tried this multiple times with the same result. I limped it staying at 20mph for about 30 minutes until a friend picked me up in a truck. I got to someplace with light and tools so I started looking at it/taking it apart. Everything seemed connected and I didn't see any leaks. Plenty of fresh oil and gas. Spark plug checked out. Idles fine with the responsive kickstarter but the electric start seems spottier than normal. I got to the CVT cover and when I took it off I noticed the clutch shoes were pretty worn off and the bell around them showed spotty contact. Ordered a new clutch assembly (not stock but a Jeremywell Driven Pulley Clutch For GY6 50cc 80cc Scooter) Everything looked the same and fit but when I took off while it seemed even it seemed more responsive than before again at ~25mph dead. I don't know where to go from here, but if you can have some sympathy for a relative newbie of scooter operation and repair I'd love to hear all your thoughts and suggestions.
Specs: 2014 Genuine Buddy 50 with about 7750 miles on it and almost entirely stock parts... thanks for reading my ramble!
Gratefully enjoying this community,
Axel

What about the front of the transmission (the variator) and the belt? A few hundred miles with the variator assembled with the spacers in the wrong order or missing is about right for the variator to start stripping or binding.

Things that die intermittently make me reach for the "electrical" section of a repair manual.
To run, you need:
Gas
Air
Compression
Spark.
As far as gas, is a hose kinked? My 125 has a vacuum-operated gas valve, does your 50 have it?
I just fixed 2 generators, one had a float valve stuck shut = no gas.
Spark: battery connex tight? CDI good?
Our 125 has a worn ignition switch which makes the kill switch not work. Maybe a switch prob?
Just a few ideas here.