I'm going to answer some of these. Please note a couple of things as you read my responses:
- I'm writing the firmware and app for McGrath Guitars. Beyond that, I am not affiliated with McGrath in any way. I had no hand in hardware.
- McGrath is compensating me for the firmware and app
- All of the below should be considered not fully validated. I don't yet have hardware in hand, so, I'm working off schematics. While it should hold true in reality, there are possibilities of this not all happening exactly as I describe here.
- Keep in mind, working on things like this are physical-space limited, power-limited, and hardware-limited. We can do a lot with what McGrath already cooked up, but, some would require a lot of new hardware and a lot more power draw.
This is one of the main benefits of the app. You will have a minimum of 2, and a maximum of 12, "Positions" to configure. Each position will be fully configurable with nearly any combination of pickups that you want.
Additionally, say you have 12 configured. But you decide you don't actually use numbers 8, 10, and 11. In the app, you simply will go in and set those to "skipped". This does kind of mentally change the ordering, so instead of 1-2-3-4-5-6-7-8-9-10-11-12, it'll go 1-2-3-4-5-6-7-9-12 as you rotate the knob. You still rotate through 9 "clicks" on the knob, but logically you're "skipping" positions in software.
This is certainly a little hard to solve through software, but, I am implementing something.
If you are sitting at a computer with the Editor open and connected to the switch in the instrument, as you physically move the knob on the bass, the Editor will also update in nearly real-time as well (something like 55ms delay). So you can do auditioning while you're programming it. The gap that remains and would require more hardware would be translating that to live so you know "Where am I?". That's where Favorite and Failsafe come in to play.
Favorite is the Position that you choose so when you press the knob, it'll switch to that setting. If you press the knob a 2nd time, it'll return to the previous setting. So if Favorite is Position 2, and you're on Position 8, you can tap to go to Position 2, then tap again to go back to Position 8.
Failsafe is Triple Press. If you do that, it'll always go to Position 1.
You're thinking of VooDoo Selector, and I swear, someday I'll own one of the... three? that have it. Somehow. I don't know how but I need that switching setup.
See above a bit

you can have anywhere from 2 to 12, and you get to now choose which positions have what configured.
This would technically be possible actually, but, not something I think we're going to implement. It'd be a 2nd cable (USB-C) that would have to be wired up to a momentary switch. Unfortunately no MIDI singaling available in hardware.
Most of this is coming (see above), except the light part. That'd require a hardware revision (and more power draw, frankly).
See my note about using it in an Audition kind of way, above. It's not perfect, but, I do think it's interesting.
There's also a few other features I'm cooking up for it. I'm hoping to have the first beta-ish level app sent to McGrath in the next ~week or so. Plus I'll be getting my own switch, and can do more rapid development once I have it in hand for direct testing rather than inferring from schematics. From there we'll iterate and refine it.
Stay tuned for more!