14 wins is an achievement regardless of whether he had a good offense around him. He's not a top echelon QB, but I think he's moved into that starter group who need run game support, which he was not a member of before.
Seahawks are about their defense. MacDonald doesn't want to run a passhappy scheme, he's a Ravens mentality coach off the Harbaugh tree. So they'll have a strong defense and give their QB a complementary run game.
I expect this draft will be trenches for them too. They probably go OL early, they need trenches help more than weapons. I'm sure we beat them 2x this year but their defense should improve again and they're a division opponent so they'll be tough games.