Zaybay, that's a great summary.
I have questions about a couple of suggestions you made, and they're actually the same question, re: NY-24 and MI-5. Are you imagining Onondaga County and/or Syracuse would be cut in two? I don't see how you avoid having an Onondaga County seat, and thus a Katko seat, especially if NY-22 is already divided up to its east.
Similarly, Gennessee County MI has more than 50% of the population of a Congressional District. This is a problem similar to the Tim Ryan's district problem - can you really get rid of that district without its population center "taking over" whatever district it's combined with? Do you think that they'd pair Flint with Lansing for a revised MI-8? I think a Flint-based legislator wins no matter what.
For NY, its mostly due to D partisanship that NY-24 is cut up. And its for a rather specific reason, its to get rid of 2 R incumbents with one stone. I believe that, to maximize their seat count, the Ds would draw Katko's base of Syracuse into NY-21, repositioning it to be more D and along the Canadian border. To be honest, I had a hard time figuring out which 2nd seat would be cut up, and thats the best I can come up with.
Its also possible, though not likely, that the second seat deleted is a Long Island seat, but the area has not seen such a decline in population that it would become the area of deletion.
For MI, it would, at first, be a Tim Ryan problem, due to how D Flint is. But the problem is that this area is trending R rapidly, and bleeding profusely. Its a seat that would make its successors tossups for 1 or 2 cycles before becoming R seats.
Of course, these are just my takes on the situation.
If CA loses 1 seat in the 2020 redistricting, Would the Non-Partisan Redistricting Commission make a bipartisan vote sink district for the GOP or Dem then?
