I still don't believe theres much chance the current Russian administration would use Nukes. Even if Putin got desperate enough to give the order, few others would commit to a suicide pack for their entire nation short of actually being invaded. Much easier to just replace the top man in such a dire situation.
My worry for a weakening Russia is if it splinters and local warlords get their hands on Nuclear weapons. Nobody benefits if they end up on black markets.
I think the ideal situation would be a Labour minority government, with the Lib Dems as king maker to force PR through.
Of course, anything would be better than the Tories, New labour was so much better than the last decade of austerity. But I really dont trust Starmer and his constant changing of position/swing rightward.