With the lone exception of Crimea, all those provinces have Ukrainian majorities. Do not think that they will take Russian domination likely. If Russia were able to militarily occupy those areas this conflict will continue. Such an expansion of Russia might please Putin and the Russian nationalists, but it would not be in the long term benefit of Russia.
I will remind you Lughansk and Donetsk territories had voted for their Independence FROM Ukraine years ago…then Ukro Nazis started bombing them- since 2014.