On my wishlist I would say...
STOP with the over reliance/wasting roster space on rookie/young guys that have limited upside when the goal is to win now. Let's limit the amount of Yabusele's, Nader's, Semi's, Bird's we have on this roster when Stevens can't play them when it matters most. Out of the final four teams (Houston, Cleveland, Golden State) all have veteran guys that you can rely on in clutch playoff moments. Stevens simply didn't have that luxury.
A shooter off-the-bench. We need someone to spread the floor off-the-bench. Just a consistent knockdown shooter type that we can depend on when the offense stalls. I recommended Joe Harris in another thread as I think he would be perfect for that role.
Smart & Rozier. I can't help, but think that someone has to go here. I don't think they mesh all that well. Rozier has a tendency to dribble too much and Smart's lack of ability to create spacing hurts him. I think Rozier would be best with a good shooter, with true SG size next to him, that's also comfortable playing off-the-bench. Conversely, Smart's also a guy that plays better when the ball is in his hands, particularly because he's so awful shooting the ball. So I think with better shooters next to him, Rozier is decent but way too streaky, would probably help him out a lot.