Japan has declared today that the southern Kurils is their sovereign territory
In the case that Russia actually collapses as a state ... which is not likely, but cannot be ruled out if they lose this war badly (lost wars are an enormous stress test for authoritarian regimes where the ruler gets all the blame, just look at the collapse of Tsarist Russia in 1917) ... a lot of territory would be up to grabs.Kaliningrad could transform to a puppet state of the EU, removing a serious gap in its territorial contiguity.Various Kavkaz ethnicities could vouch for independence.Tuva (ironically, where Shoigu comes from) is a Buddhist nation that fits into the Mongol-Chinese cultural sphere better than into Russian one.Vladivostok used to be a Chinese fishing village once, and the Chinese hate the old Unequal Treaties.Sakhalin is a part of the Japanese archipelago.Vyborg (Viipuri) and Pechenga (Petsamo) are formerly Finnish territories and even though the irredentism has subsided, they could still be valuable economically. Vyborg is a major port and Pechenga gives access to the Arctic Ocean. Their reconstruction would be a huge money sink, though. Much like reconstruction of the DDR after reunification of Germany.