I know what you mean about that expression on his face.
People have been saying that Derek will be a comedy drama and not a sitcom, and that's kind of the problem.
If this is a comedy drama as opposed to a sitcom then that 'ape brain' face he's pulling looks like it could be a problem.
If it's a sitcom then fine, you could probably get away with it, but if it's a comedy drama which is usually supposed to be a bit closer to reality I can't see how that stupid face he's pulling is going to work. I just can't imagine me taking him seriously as a real character if he's doing that.
I'll give it a go as I tend to like the things he has done so far in varying degrees.
From the trailers I thought the exact same. Not sure why he feels the need to put on that face.
Saying that though, Billy Bob Thornton got praise for doing similar.