Hollis-Jefferson is not a shooter. Indeed, he's almost a non-factor as one. Aside from, if we're being generous, a fairly consistent 12 footer, Hollis-Jefferson is little other threat on the jump shot, and does not have much potential in this area with his current form. He does at least shoot 70.7% from the foul line, which is not bad, aided by a quite contrived wiggle in his pre-shot routine. But the wiggle can't be adapted to the jumper, and so a wiggle-less RHJ is able to be entirely left alone from the perimeter.
Every other part of the game, however, has plenty of potential. Strong, long, fast and athletic, Hollis-Jefferson defends multiple positions and plays with great energy on the defensive end. He plays hard on the offensive end, too, but his skill is underdeveloped - lacking a jump shot with range (as mentioned above), demonstrating little in the way of ball-handling ability, not posting up, and not in any way creating much offense other than by running the court. Hollis-Jefferson is also not the best finisher when he does get looks at the basket that aren't dunks, although he does attack defenders looking for contact, and does at least create these opportunities through cuts and hustle. But in order to be a slasher, he has to develop his handle beyond being the straight line driver that he is now, and improve his awareness so as to not barrel in recklessly.
The defensive end is the calling card and likely always will be. Always with great energy, Hollis-Jefferson stays in front, bodies up, uses his length and reading of passing lanes to recover for blocks, and has a knack for clean stripping drivers. He stays in front of smaller guys and smothers them on the perimeter, closes out quickly and with his hand up, and bodies up the bigs with core strength that it does not look like he has. In theory, RHJ can defend every position - that makes him a 3 by default in the NBA, as do his measurements, but a small forward with defensive versatility to go both bigger and smaller is exactly the type of small forward the NBA wants.
These improvements are required more than desired for Hollis-Jefferson, if he is to stand out from the Julian Wright types that have gone before him, players did not develop these skills and found themselves soon out of the league for the next crop of the same type of player who might. The idea of a multi-positional, defensive-mind, transition-and-cutting athletic presence is nonetheless a nice one. Hopefully RHJ keeps up the intensity and is exactly that.