I don’t see much of a case for RHJ, frankly, other than just generically that they would benefit eventually from experienced wing depth. You have Semi as a defensive-oriented deeper bench guy already, and Semi is a better shooter. If you have some scouting reason to see upside, ok, but I don’t see it. He to me is a guy you might like to add mid-year, but not sure I’d use the slot this way now.
There’s a case for Harrison—-the shooting could be real (FT jumped up as well) and if so he’s an upgrade—-and if it‘s not he’s a smaller RHJ. YMMV, but advanced metrics have him as a Kris Dunn-level defender. That he remains unsigned suggests the league is guessing that’s SSS though. As Cellar Door notes, there’s a lot of reason to worry the shooting is not real, so you gotta really dig into the scouting there to see if something changed. There’s a story there that he is really additive but it’s a SSS story. I like the upside but haven’t scouted the guy.
Robinson is interesting, but you worry that he’s a bit duplicative of Nesmith. To me, the useful depth is valuable and I’d take the shot but I tend to think Celts will not. There’s not a lot of upside here either—-I think he’s a playable wing who can shoot.
In my view the 15th spot is where (Ideally) you gamble on upside now, and where you want (by trade deadline) to have gotten credible depth you can actually play if you need to especially in playoffs where younger guys can struggle. I‘d personally have liked a Bane type guy there to see what he looks like for a couple months and then make a call among he, the two-ways, Semi, etc. if you need to add someone else. But that ship has sailed. So now the question is whether to add the depth now or wait and hope you can add later. It’s most easily available now but you have to like the guy to bother because it does impact development of other players. My issue with Green in the slot is I don’t really buy there’s a lot of upside there, so you neither get playable depth nor upside, but they appear to see more chance he develops into something. I hope they are right, he was fun pre-season last year.