I agree with everything you said until the end, Torreira is part of the problem like the rest he shouldn't be absolved of blame because he runs around a lot and is a fan favourite.
Torreira lacks physicality and stamina, our midfield gets bypassed a lot because he gets out of position trying to chase a tackle. Our whole team has chemistry issues.
I said he can be upgraded on but he shouldn't be the first to be upgraded. Put some pace in midfield with him and forwards who can receive the ball to feet back to goal, or run behind and Torreira instantly looks better.