I think the proposed peaceful settlement, were Russia withdraws from everywhere they occupied except Crimea, which is demilitarized, is possibly the best outcome that can be hoped for. Although the Ukrainians may consider it an inviolable part of Ukraine, it has only been so since 1954 when it was unilaterally transferred, under Khrushchev. Ethnicly Ukranains are very much a minority there, the main population was over 60% Russian and Russian-speaking, even before any population transfers since being annexed in 2014.
Demographics_of_Crimea
You have to consider practicalities and be realistic. The reason the allies were able to put the senior Nazis and war criminals on trial and execute them for war crimes was becacuse the allies demanded unconditional surrender, and enforced it - Germany itself was invaded and occupied. Even Japan only had very senior leaders put on trial despite unconditional surrender. Are we going to rely on the Ukraine getting to Moscow, because I cant see any Russian regime accepting it otherwise? So Putin and his cronies being put on trial as a demand of the west is not going to happen. Weakened though, he may be put on trial by the Russians themselves, in time.
As for militarily... the Ukrainians may well be able to take back the Donbas, if Western support continues. If. But with the west entering recession and the possibility of a Republican administration in the USA in two years, it's a big 'if'. An opposed crossing of the Dnipro River looks to be a big challenge... and after that, advancing down into Crimea through that narrow choke point, onto the peninsula... long supply lines, with Russia having some dominance in the air and on the black sea... very formidable. And then holding it, frozen in, like the Korean war? Whereas a peace deal makes some kind of NATO membership for Ukraine at least possible.
