I think the full backs license is directly relative to how well you're able to defend. When centre backs play forwards onside in behind you, you've gone an obligation to not get caught out first and foremost and our left side is the most secure part of our defence at the moment. Even if he's not contributing as much going forward, he's always been a bit vulnerable. But he's experienced, reliable and probably has the cleanest underwear of our defenders.
Cuco and Holgate can go down wing and create more play and chances, but I'd still take a single Baines cross to 5 or 6 crosses from our right back options. We could yet see Baines given more encouragement to get forward under Unsworth.
I would also think he might bring through Garbutt. He was supposed to be challening Baines last season per Martinez, but Koeman didn't fancy him. He might give the team a better balance or Baines a reason to return to attacking form or more willingness to bust a gut, when he gets a chance.