I have used splits for a long time. An improvement I swear by for thumb clusters is making the keys farther from me taller. I have no idea how I'd hit them without that. My keyboard is a Keebio Iris [0]. The thumb keys closest to me have relatively low-profile DSA key caps. The keys above them are SA (edit: row 3). I think this is a decent avenue for keyboard customizers to explore to make their thumbs have a better time reaching up a row.
The Glove uses low profile switches though, so I have no idea if different height caps are even possible with those.
profiled keycaps are absolutely possible but I haven't seen any out there. someone wanting that would probably have to 3D print their own, or at least some kind of spacer
The Glove uses low profile switches though, so I have no idea if different height caps are even possible with those.
[0] https://keeb.io/collections/iris-split-ergonomic-keyboard