I think you are mistaken to believe, a country as natural-resourceful as Russia is in Ukraine for the purpose of natural resources.
For Russia it is about protection.
If say Russia would be able to permanently place "security-troops" on the east-bank of the Denjepr it would have reduced its "Ukranian flank" by 50% in length. If the west remains NATO-free, perfect from their standpoint.
From looking at former election results, the eastern bank as well as the southern steppe, would be relatively safe for permamently stationed Russian troops.
For Russia it is about protection.
If say Russia would be able to permanently place "security-troops" on the east-bank of the Denjepr it would have reduced its "Ukranian flank" by 50% in length. If the west remains NATO-free, perfect from their standpoint.
From looking at former election results, the eastern bank as well as the southern steppe, would be relatively safe for permamently stationed Russian troops.