@ArabellaScott
Yes, it's counter intuitive sometimes. It seemed that voting for the party you want can somehow actually be detrimental to them. If anyone has guidance on how to do it, I'd appreciate it ...
Don't over-think it. It's a fallacy to think that all electoral systems are as susceptible to tactical voting or unwanted outcomes as FPTP. This one's fine except for the closed lists.
(Aside, I see the Woke/SNP have been at that Wiki page linked above:
With closed lists, party-list candidates may become puppets for the party leadership, or may add diversity to the party's elected members.
They're diverse puppets. 
)
This is two votes. First constituency one is plain FPTP, with the familiar problems. Vote for minor parties can be wasted.
Second one is regional list-based proportional, but seats already obtained through FPTP are taken into account. (Actual votes in constituency FPTP, including wasted ones don't matter)
As an individual, your 2 votes can't really interfere, or it's spectacularly unlikely. Attempts to be "tactical" across the pair could backfire just as much as not doing so. Just think of it as two independent votes.
For FPTP constituency, you may want to vote tactically and think about split votes. For list regions, it's proportional, you can pretty much always just vote for your favourite.
If your single issue is independence, it's SNP in the constituency, and Alba in the region. You just want to maximise pro-Indy MPs. Assuming the SNP get more than their fair share of seats due to FPTP in the constituencies, as before, the list PR calculations will balance the parliament against them, giving list seats to any other party more easily. A regional vote for Alba is more likely to secure an extra pro-Indy seat than a vote for SNP - an SNP regional vote is likely to be wasted.
(And if this is "gaming" the system, it's the SNP who have gamed it by getting more than their fair share in FPTP. Their excess cannot be fairly deducted from Alba's share any more than it could be from the Greens).
If your single issue is anti-independence, then it's probably Labour in the constituency , and then whichever Unionist party you prefer in the region.
If your single issue is minimising Woke anti-women parties, I think it's Conservatives in the constituency and Alba in the region.
I guess most of the constituency seats are so secure SNP/Labour there's little chance of the Conservatives actually winning them, but politicians do (eventually) have to pay attention to decreased majorities.