Not withstanding the usual whataboutery and false equivalences, the moral argument for supporting Ukraine is pretty watertight IMHO, it’s a rare example where the morally right thing to do is also good politics.
Mike Martin, whose analysis of the war has been pretty solid so far, has suggested that Tokmak is likely to be where it all kicks off again.
Looking at the map you can see his logic; the railway line that runs from Crimea, through Melitopol and then Eastwards to Russia takes a deviation Northwards to run straight through Tokmak, bringing much closer to the front lines. Based on that alone, Tokmak is the obvious easiest place to push towards if the Ukrainians are trying to get the railway within HIMARS range.
With the Kerch strait bridge still far from repaired this railway line is the key supply route for Crimea and the Russian forces in the Kherson oblast. If Russia wants to hold on down there through this winter they really want to keep it open.
However, the sheer obviousness of this and the fact that the Ukrainians have repeatedly proven the be highly adept at feints and other such misdirection means that any move on Tokmak could also be designed to draw troops away from a much bigger move elsewhere, just as they did in Kherson/Kharkiv in early Sept.