I think the 2.4ghz is going to be the most rare feature. I found essentially one Etsy seller (https://www.ebay.com/sch/i.html?sid=vooooodooooo&_pgn=1&isRefine=true&_trksid=p2349624.m3561.l49496) and then the dygma. I think since Bluetooth in integrated in to microcontrollers, this becomes the simpler solution.
I experienced this at first with my ergo, and for me it is currently not an issue. There are some minor issues with some of the super common keys that are in different places (like enter which is currently on my left thumb on my ergo, and right pinkie on normal keyboard).
Starting with my ergo was also very disheartening (for me I went way too extreme with my switches which killed my accuracy for a month), but I love it now.
This is a nice clean layout! I appreciate that it isn’t trying to be tricky, but just lay everything out simply. The only part I’m not really getting is the equals sign relative to things like plus and times? Seems like typing equations, and things like += or *= kinda awkward? Beautiful all the same.
I notice all the 1.5u choc caps are out. I assume there is no way to make those for the giveaway?
Not sure about your timeline, but the Naha Create is currently on Kickstarter, and I think might satisfy all these requirements: https://www.kickstarter.com/projects/naya-create/naya-create
In general, I’m not sure how easy it is to have multiple pointing devices? For the example you give of a coarse and fine pointing, the most common solution is to have keys that switch between coarse and fine pointing on a single trackball. I’m not sure if QMK can support two pointing devices at once (without significant customization).
For single pointing devices, I’d check https://bastardkb.com/ . They are also very slick devices, but can get pricy.
I have a pimoroni trackball that I use for a variety of things which might feel good on some knobs too. I think that text cursor will likely feel pretty good, particularly if your encoder ticks while twisting. Then you could make one tick equal one arrow key press, and you dial in precise cursor location.
HolyKeebs just announced their new keyboards with integrated trackpoints: https://holykeebs.com/pages/trackpoint . Something they do that is really cool is build them into the microcontroller itself, so if your board has the microcontroller in a convenient place, you can add the trackpoint straight to an existing device (already sell it for pimoroni trackballs, trackpoint in Q3). I have a Corne from him with the pimoroni, and I enjoy it, but the pimoroni is not a full mouse replacement for me.