Most of our attacks are through the wide areas no matter who starts in the middle and everybody we play there can pass the ball out to the wings effectively. I think it's more important for Silva to get the defensive balance right at the moment.
Gana and Gomes tend to get overrun without a third proper midfielder alongside them (this has been the pattern since December). Sigurdsson is generally positioned too far forward to help them out.
With Sigurdsson starting, I'm starting think we're better off playing a second defensive midfielder. It makes us stronger without the ball and the "loss" in distribution hardly matters because we're playing through our wingers and fullbacks anyway.
And when Silva does manage to "get away" with Gana-Gomes-Sigurdsson like he did in the first half on Saturday, it would be nice if he learned to shut the game down while he's ahead. Sigurdsson off, proper midfielder on. Now you have an extra body to shield the defense and get a hold of the ball further back, which can help relieve pressure.