Due to the 3D nature, it is very hard to mock up with a few pieces of paper.
One thing to note is that the Glove80 thumb cluster plane is at a very different location and angle, compared to the the Kinesis Advantage thumb cluster plane. In fact the Glove80 thumb cluster plane is much lower and slant down gently (nowhere as much as DM) towards the opposite half. OTOH the KA thumb cluster sits significantly higher than the keywell.
Due to the thumb plane difference, "the glove80 cluster placement forces my hand on a higher position and requires the thumb to stretch more" is not the case in reality for me.
I would definitely reposition the thumb cluster on the KA to be slightly lower (no more than 1cm lower really), however I didn't find this to be a problem for me.
I rest my hands with the pinky/thumb at about 15' (that is, the hand is is not with the palm flat but at about 45" compared to the keyboard). If I extend pinky and thumb, they're naturally on the same plane.
If I could tent the halves though that 1cm of difference would be nice.
On the kinesis I can hit comfortably ctrl+alt + "=" (and pretty much any other key on either half) with thumb+pinky, on both halves. Holding shift is also entirely possible with pinky or ring, even in combination with ctrl/alt/ctrl+alt and while typing with the remaining 3 fingers.
Seems a stupid thing to do when written, and maybe it is, but hey .. emacs, and I'm doing it with ease actually. I normally chord the modifiers with one hand and type with the other, but if there's a weird combination I'll just do it with a single hand too.
I could definitely 3d-print an entire glove80 mock if I found a model.
For a long time I've been pondering about just 3d-printing a modified dacytl to fit my own preferences, but it's one of those things I wish to just pay for, have some QC without wasting time, and be done.
One thing to note is that the Glove80 thumb cluster plane is at a very different location and angle, compared to the the Kinesis Advantage thumb cluster plane. In fact the Glove80 thumb cluster plane is much lower and slant down gently (nowhere as much as DM) towards the opposite half. OTOH the KA thumb cluster sits significantly higher than the keywell.
Due to the thumb plane difference, "the glove80 cluster placement forces my hand on a higher position and requires the thumb to stretch more" is not the case in reality for me.