Only needs to be their 4th mid to score very well for mine and looks like Swallow has stepped aside to allow that to happen, goal kicking mid/forward has some serious ceiling about it he's in my side currently.
As AngryAnt mentioned, we won't really know now in the pre-season games, as I assume Swallow will get his standard 40-50% CBA's and Flanders will have a CBA boost with Touk out.
Definitely if Flanders is the 4th MID, I think he would benefit, I still see him as the 5th MID though.
I could see GC having a 5 man rotation this year (some talk of it pre-season) rather than a strict 4 man rotation.
See Round 22 last year (Touk 73% Rowell 73% Anderson 60% Swallow 40% Davies 43%) which was a bit of a change from their heavy 4 man rotation.
Still a lot of guess work I think