I'd play Fraser over Welsh tbh. They both lose the ball fairly often but at least you get a decent range of passing from Fraser in return, whilst not prolific he'll chip in with a few goals over the season compared to Welsh and he's still only 21 with plenty of time to work on his deficiencies.
Ideally we'll get a replacement in for Bannigan who is solid enough defensively but can still get forward so we don't need to go with 3 central midfielders all season again with Fraser and Welsh providing back up. That means we can go with 3 attacking midfielders in Erskine, Amoo and one of Edwards or someone like Nesbitt if they come back. Nesbitt was in the pub on Saturday and said he'd like to come back and get some games but I expect he'd say that regardless.