As I pointed out in the other thread, the total length of the light would be the same regardless of which cells you used. The TK4A is 115mm long, about the shortest it can be and still be ergonomic.
A 65mm long cell can have the same total length as seen on the NE01. So the size “issue” is a moot point. Ergonomics will determain the minimum length anyways. With an e-switch light if it is too short you will not be able to access the switch without repositioning the light every time.
As far as the quote. So what you are saying is that you don’t care what the light is as long as a new driver is designed for it? A driver that would be useless in any other light as it would be too large for any normal lights and too small for any SRK style lights?
Not to mention that such a driver could cost as much as the entire light and thus almost double the cost of the light.
If it is primarily an AA light, then why make it? The TK4A is good enough and we can’t improve on it except for a better UI since the AA’s themselves will be the limiting factor on brightness. Way easier to just build a new driver for that light for people to swap in.
If this is something you have your heart set on, then fine. Doing something because you can is as good a reason as any.