This will effectively make the "6 switch" rule obsolete but I doubt many 1&2 family are using that rule these days anyway. I suppose there are existing split bus panels out there but they are overdue for an upgrade and when that happens they will bump into this rule. It will increase the sales of "Meter main" panels I suppose. The only debate I have heard on the down side is you might have kids tripping the main as a prank. That could be devastating on an unoccupied house in the winter.
There is no problem daisy chaining GFCIs, I do it all the time with the cord mounted GFCI I use when I am working outside. The circuit has or is supposed to have a GFCI but I still like having one I monitor and test regularly. There is also a GFCI on my boat lift in addition to the GFCI feeding the circuit. This is a very mature technology and I am skeptical of any claims of false trips unless the GFCI itself is bad. That is usually a hard failure. (won't reset, even with the downstream circuit disconnected). You are right, it is beyond the code requirement but it should work fine.
Yes, there is some abuse of 110.26 by both some inspectors, some 'plant safety guys' and some sparkies.
The disco up above the drop ceiling, I have no issue with, in sight of the equipment served, and IDd as to the source of the feeder/branch circuit. I just completed an HVAC replacement project at a utility training center with 68 AHs all above the drop ceilings, with no issues.
As to the LOTO, yes, I have come upon both extremes, overkill, and 'where is it'. Tape is not a LOTO, no matter what you write on it. One facility has LOTO on all new installs until inspections are completed, 6 locks are common.
H2Os case is just the AHJs decision. A talk may help.
The bottom line is, "what does the label say" . You don't need to wire any motor load for the locked rotor current because it is only there for a second or less. We wire for 125% of the full load amps. In a complex box like an HVAC system the industry engineers evaluate that box and give you a label for guidance. As an electrician or inspector we should just believe. You can use a #12 for that if everything is rated 75c (breaker, conductors and HVAC lug)