It looks like the driver cavity is about 19.3 mm inner diameter and about 2.5 mm deep. The tiny85 is the tallest component, at about 2.0 mm, which leaves 0.5 mm empty space to the shelf. In theory, Hank could make that 0.4mm or 0.5mm shallower to speed up thermal regulation response, but there might not be enough room for the wires.
I agree the UI can make a huge difference. That’s why I’m excited about the firmware being fully open-source. It can have any UI you want.
As for Indigo, everyone can use source code without any restrictions. There’s no licence but author is not against, in simple words - do what you want
Does this mean Indigo is public domain? Usually “no license” defaults to “copyrighted with all rights reserved”, legally. But if the author states that it is released under public domain or CC0, I can include it in the repository.
(note: “public domain” and Creative Commons Zero “CC0” are equivalent)
I suppose I could include it anyway, but it would still need a clear license of some sort. For example, I have DrJones’ luxdrv which is CC-BY-NC-SA… even though the NC (non-commercial) part causes trouble. The NC part means I can’t even look at the code without risk of being sued, because people sometimes sell the stuff I make.