I think Dykes will be a stick on to start as we're probably going to have to rely on lumping it forward and playing off 2nd balls, he seems the best candidate for that role although we saw his technical limitations a bit last night.
I would ditch McGregor for Gilmour or Armstrong, McGregor spends most of the match running into space 10 yards from the centre backs so he can pass it back to them. Clarke seems to want to deploy him as a deep lying playmaker but McGregor looks afraid to even attempt a risky pass. Midfield should be either McTominay and Gilmour as a 2 with McGinn playing in front of them or McTominay as the sitter with Armstrong and McGinn more advanced on either side
I'm also concerned Christie will be starting, on the basis that he scored 2 decent goals in the last 3 years and Clarke seems to rate him