> What kind of mouse or trackpad is everyone using with these $xxx - $xxxx keyboards?

Mice with holes. Your mouse must have holes.

https://i.redd.it/i5s6j18i3hp31.jpg

https://i.imgur.com/DSW0lvH.jpg

https://www.youtube.com/watch?v=14d68Wgwevs

https://en.reddit.com/r/MouseReview/

None of those look nearly as good as the GITs inspired, Masamune Shirow designed PS/2 serial mouse I own (only as a collector's item - I don't use it). Found it cheap on Ebay years ago. Today I don't even want to think of what it would cost (I'm sure it's become a collectors item of some sort).

That looks like a cleaning nightmare waiting to happen.

If I need to clean a mouse that I've been using for less than a few years, I am going to reevaluate my personal hygiene. After that, it's going in the trash.

What cleaning? You just buy the new one.