It's positive. Really positive. However we need our best players against Serbia and Tierney is our best (for me). He needs to be at CB I think. His passing out is better than McTominay's and at Arsenal a lot of attacks start with him or go through him. The 3 CBs are hard to choose now though.
McTominay/Jack vie for CM and then I don't really know what to do with McGregor and Armstrong.
I'd go with
Marshall
Gallagher Cooper Tierney
O'Donnell Robertson
McGinn Jack Christie
Fraser
Dykes
Turnbull, Gilmour, Campbell, McCrorie, Hickey and a few more will only make that squad stronger over the next year or two. C'mon!!!!