Zucc is good at playing with Kaprizov. Not everyone can play with great players. He is smart, and an asset on the PP. At 4M, I'll take him, especially considering the lack of skill we have up front otherwise, at least till Rossi, Ohgren, and ? develop.
Having said all that, I think Boldy should be playing with Kap, and Zucc has to prove that he can make a 2nd line work playing with Rossi, and Ohgren/Hartman/?. So far, he and Rossi don't seem to have a lot of chemistry, but they are both smart players, and might be able to figure it out. If Ohgren is able to find his shot in the league then he might be the answer, but i think this year will be more of a developmental one.
Zucc is definitely on the back 9(more like final two holes) of his career, but so far, he has been a net positive for the team except for that awful first year when he was playing with an injured wrist. It's not like we have a tone of options available for the top 6, as is.