I know that this thread is dead as a dodo, but in the interest of accuracy I just have to post.
But fork me the political situation with the SNP seems to be a real shitshow in reality. At least in the rest of the UK any party that makes a mess of things can get voted out. The Tories arses are dangling way out over the cliff edge from my point of view. I'm worried about Starmer the fence sitter not knowing what an adult human female is when he gets in. My point is in the rest of the UK the party in charge can be changed through a general election.
In general, a "snap" general election is easier/more likely for Scotland (Holyrood) than for the whole UK (Westminster).
When a UK PM resigns, the new party leader automatically becomes PM (subject to royal assent). But at Holyrood, the FM must be elected by a majority of MSPs. Because no one has a majority at Holyrood, the SNP will need at least one other party's MSPs to support their candidate. (Which is why there's so much speculation that the Greens might nix this or that SNP leadership candidate - but the SNP can get their person through with the help of any other party or a random assortment of rebel MSPs).
If no candidate wins a majority, or if the winner isn't considered capable of maintaining the confidence of the Parliament, there's no FM. If there's no FM 28 days after the current FM resigns, there's an election.
Also, the Scottish Parliament can still trigger an election by a 2/3 majority of MSPs. The UK Conservatives used their majority from 2019 - on the strength of which they have had 3 PMs, the last elected by nobody - to change the rules in the UK so that only the PM can call an election. When Truss and then Sunak opted not to call one, that was that.
Neither the UK nor Scotland is a "one party state", but I'd say the UK is functionally closer at the moment. Of course, the UK also has the check and balance of a second chamber in the HoL, which Scotland does not.