Mushfiq is batting very low down the order, and it can't be helping much. Bangladesh needs to go into the second test with a proper 4 man bowling lineup, and drop a batsman like bashar who is done and should be gone. This will move Mushfiq up one slot and I think you will get better returns from him.
It's his wicket keeping that is not up to Pilot's level for sure, at least not yet. But dropping him in the middle of the series will not accomplish anythig and is highly unlikely.