We're not that important or interesting is precisely the reason why we would be a good target for a nuclear strike.
It would be foolish for the Russians to attack America directly. If they launched some nuclear weapons in our direction instead, it would show America that they are serious about using them, but wouldn't necessarily lead America to retaliate. NATO be damned, member states will still look after their own interests, and a Britain destroyed by nuclear weapons is no longer a useful ally.
While I think it's unlikely the Russians will target us, probably less than a 10% chance this year, the fact that we'd only be able to reply in a very limited way (one nuclear sub out on patrol could target Moscow perhaps but the response would be nothing compared to what the Russians could target us with) means we'd be a much safer target than if they went to American territory.
Whilst it's tempting to hope the Russians will launch nuclear weapons upon Poland or Finland, purely from a Russian point of view that doesn't make much sense because geographically those countries are much closer to Russia and there would be a greater risk of radioactive fallout being carried back to Russia.
Also, those countries have large, sparsely-populated areas. That's another key "benefit" of attacking the UK, it's much more crowded.
Like you I'd prefer it if the war was kept on the fringes of eastern Europe, but don't think that our insignificance will protect us.