Hello swathdiver!
Update is: all is good in 6L80-land. I am very happy with the work I did. I have peace of mind in that the fluid is flushed and fresh, the ZIP kit has addressed several known wear issues, the pressure switches are rebuilt, and the BlackBear Tune had made it that much better.
I cut the remote hydraulic filter apart some time ago, and found absolutely ZERO metal or debris in it.
The transmission just does its job. It runs cool, shifts firm and quick, and is trouble free.
Thinking about it, I would have gotten the Tech 2 first, then done the work. That would have saved me the hassle and embarrassment of having to go to the transmission shop and not understand how long it would take.
Other than that, nope, I would not have done anything differently.
Now...this is my results, on my transmission. Mine only had 12*,*** miles on it, fluid looked OK, and unit shifted fine. Meaning I don't think it had any issues. I don't know how all this would work on a higher mileage unit that may or may not have issues.
Though, couldn't hurt.