That was a long read. I will respond only to the points that stood out for me.
1) Civilian casualties remain light
This is true. The Russians are not carpet-bombing and the accusation of war crimes probably would not hold up as it requires clear intent. Most of the civilian casualties are tragic collateral damage by a careless or incompetent Russian military machine that lacks the discipline and precision of better armies and is more interested in winning this war than worrying about civilian deaths.
2) Zelensky and Biden made mistakes in the build-up to this
Definitely, the talk of NATO membership was a red line for the Russians. But it is clear that Putin has been planning this for a while and was just looking for an excuse. Putin was not looking for a compromise coming into this. His initial objective seems to have been the reunification of the triune peoples of Russia, Belorussia, and Ukraine in a single nation again. Gazprom obtained a majority share in gas containers in Germany allowing it to run down supply. This is clearly years in the planning.
On the Historical Unity of Russians and Ukrainians - Wikisource, the free online library
3) For NATO to close the skies would be an unnecessary escalation
This is clearly true as it would involve taking out Russian airbases and missile capabilities inside Russia as well as across Ukraine. It could be done but the risk is nuclear war and is not worth it for anyone. The Mig-29 issue is a case in point. They still have airfields open in West Ukraine and are even shooting down Russian aircraft even though they are flying old stuff. But sending these planes to specific choke points would be problematic and a death sentence for the pilots. Giving the Ukrainians Patriot systems right now to shoot down planes at 50000 feet where the Stingers and NLaws cannot reach would also be an escalation.
4) If Ukraine had nukes they could have stopped Russia from invading
This shows some ignorance of the Budapest Memorandum. Russia respects Ukraine's territorial integrity so long as it does not have nukes. Zelensky made a mistake in April last year when he suggested that Ukraine would develop them if not allowed into NATO.
5) The Azov battalion and Chechyan extremists are being used by both sides for the hand to hand street fighting
Nazis are now only a minority of the Azov recruitment but there is still an influence. They are an effective fighting unit so better on Ukraine's side than not at this difficult time. Also, they have been fighting Russians for much of the last decade in the Donbas and now in Mariupol. If these guys want to go head to head, then I guess they could wipe each other out. Maybe the world would not miss them as much as other soldiers.
6) A compromise is probably the best way to end this
I agree and the concession of the Donbas, recognition of Crimea, saying they will not join NATO and maybe the land bridge to the Crimea look like being at the top of the PLan B Russian concession list. But the Ukrainians increasingly believe they can win this outright. I think they are wrong and this will come down to a compromise. With German and general European remilitarisation the EU may adopt a security dimension and welcome Ukraine in. This would be painful and costly for the EU as Ukraine is massively corrupt and undeveloped and would require major rebuilding costs also. But it might be a compromise that could solidify the borders once and for all. Putin has not yet reached the point where he understands that a compromise is his only way out though yet.
7) We should support neither side because both are wrong in some way.
Noone is righteous not even one. But I am 80-20 with Ukraine on this one. They were invaded and they are the victim here. Russia's action is illegal and its historical case is not enough to undermine the basic free will choice of the nation they have invaded to set its own path to the future.
