I would maybe be tempted to restrict Gallagher's getting forward quite so much, that might result in a better balance - it was great what he did yesterday in a "must win", but we look so open at times it is painful, and Sawyers still stops tracking his man back too often, he let the full back go free for the one he blazed over the bar from about 10 yards.
YESS! A confident and on form Sawyers with Gallagher as part of our midfield, could add a bit of real quality. Gallagher, good as he is, might be far more effective if he 'times' his forward forays a bit better. Sawyers would also benefit so much if Gallagher stays deep a bit more, to give a bit more defensive cover, instead of trying to be everywhere at once. Playing like he does is Gallagher's natural game though, and it would be a travesty to restrict him too much.
Same with Sawyers, work-rate and defensive cover are key parts, but Sawyers strengths are also different and he should be within reason allowed to play to them.
It is as you say Mulligan, about giving us a better balance, Gallagher would also last the full 90 better if he didn't try to cover quite so much ground and let the game come to him a bit more instead of chasing it. It's probably about experience and when he gets this to add to his skill and athleticism he really is going to be some talent. We must enjoy him whilst we can.
Sawyers and Gallagher together though could form the basis of a very workable midfield for this season.