I went with SRAM’s EX1 cassette, chain, derailleur, and Shimano Saints. No chain Breaks/drops, shifts clean, great breaking power. Thought I would chime in since you are planning to make some changes. Let me know if you have any questions about my setup. Happy to help. PS my top motor mount bolt came completely off, so it’s a good idea to get covers off and check once and a while.I am about to change a number of bits on the Levo, brakes, wheels, cassette, chain.
I am not happy with brakes, the Guide R are no where as good as my old Hopes, the XD freehub I am also not happy with, so going with a Hope Shimano setup.
I am going to try the KMC e-bike chain, to he honest the PX01 was ok, just thought I would try something else.
I have taken the motor out once, easy enough job, the upper fixing had not been torqued up properly after warranty work so whilst I was doing that, gave it the once over and a clean.