When KG comes back, and if Bass continues to start, I'd like to see Shav be the 1st big off the bench. Heck, I might be inclined to have him be the 1st player off the bench, just because I don't like Bass at center.
KG is almost always the 1st player subbed for. If we bring in Lee at that point, and slide Green to PF, it moves Bass to center. I'd rather wait until Pierce comes out and then sub in Lee/Terry.
The other alternative, would be to sub out KG and Bass simultaneously, and bring in Shav and Lee. That way when KG is ready to come back in, he just subs for Shav. When Pierce is ready to come out, Bass replaces him, moving Green back to SF.