Seriously - that’s not the problem. Tying together into one state with ex-Soviet unitarist culture so many different areas with natural riches and subservient population is bad.
I’d rather split both Russia and Ukraine into equally-sized (population-wise) pieces and have them form confederations where unity is wanted. (Fuck, that’s another USA)
Since Ukraine can’t hope to have a victory that will solve the threat, I think Ukrainians should be interested. Their country would split into like 3 pieces which are different enough anyway.