In short, no.
Greens are hardly 'opposition'. They are a more cuddly and eco friendly snp, but further left. It is PR in scotland, so they will hoover up the second votes i magine.
Last election, they picked up a fair few and even first choice votes from snp voters that felt snp were in a string enough position that they could afford a vote share, on the back of their 2015 g.e results and confidence. I wouldn't think that may be the case now, but they are still a small but important player if it hets marginal.
I keep wishing every bloody election that lib-dems would cut the crap and put a decent candidate forward, and be a bit more convincing. Because, they have some really good policies. But their inability to do so, and their daft entrenched stance (which many senior figures actually disagree with) of following the party line and defining theselves as a party for the union, is what will stop them getting the middle ground votes. Labour and in particular the Torries will discredit them as a 'non-credible' party of the union, each claiming that is them, and will fight them on that over policy, where lib-dems would win hands down. And likewise the snp will do the same, bit from the other side of the independence line. Really, if they cut the cord with head office, which is fucking uselsess down south anyway, and took a more neutral stance on independence, they'd have a decent chance at getting meaningful numbers.
Labour are fucked. I don't see a way for them. Their votes are divided up between the torries and the snp (or greens, butbsee above), mostly based on a stance on independence, but not exclusively. there are margins of greys there.
Torries really have nothing to offer, other than they are not the snp, and they can claim to be the strongest of the unionist parties, so a vote for them is Not a vite for the snp, if independence is not what you want. They don't even pretwnd to offer up anything else. Put up with crap unpopular policies by the party line that even They don't agree with, but for less chancenof another referendum.
The snp, hardly needs commentry, kinda all been said before.
Does that help?
(in some ways this is where Ban-jani is right, in part, with his 'divide and conquer comment')