To be honest, I have pretty low expectations of Young and Turner.
Young
Young looks like he has nice size/length, but he seems to have fairly average athleticism and a significant lack of physical strength.
Offensively I like his jump shot, but I'm not sure he has the ball handling skills or speed/strength to get to the basket and finish at the NBA level. He passing skills seem par for the course too.
Defensively so far he seems pretty limited as a result of so-so lateral quickness, lack of physical strength, and what appears to be pretty average defensive IQ. His rebounding skills, again, haven't stood out.
I think he could develop into a solid rotation player one day, but I don't see the star potential that others are crying out about. I think his one excellent skill is his jump shot, and he'll probably earn playing time late in his career on that alone. I might be proven wrong - I hope I am.
Turner
Turner I think is limited by his basketball IQ.
The kid has talent - good size, very good ball handling skills, solid passer, good midrange game, improved defense and an ability to get to the basket. But tries too hard to force things, rather than letting the game come to him, and he struggles badly under pressure. Any trap / double team of Turner is an almost certain turnover. Really, he causes it himself most the time - runs straight in to two defenders, then tries to get fancy, then loses the ball.
For Turner to take that next step he needs become a consistent three point threat (at least a 35% shooter from three) and needs to learn to let the game come to him - but those have always been his limitations, and it's hard for a 'leopard to change it's spots'. Unless he does those things he'll remain what he is now, which is a solid backup / role player who you can bring off the bench at multiple positions, as a bit of an offensive spark plug (if he is on that day).
I'm encouraged by his improvement this season (because most viewed him as a lost cause after his stint in Indiana) but any hope that he'd justify his high lottery selection (or even close to it) is I think long gone. I doubt Turner will ever be "starter on a good playoff team" caliber player, but I think he could be a nice role / situational player.
Smart
Smart I think is in a different position. He doesn't just have solid physical gifts, you can see he has solid basketball IQ and an elite motor / work ethic. Those two things can take a player a long way. As 20 year old rookie who isn't a natural PG, he's already putting up solid assist-to-turnover numbers mainly due to the fact that he doesn't try to be too fancy - he makes the simple play, and he rarely turns the ball over. He's also shown he has potential as a shooter (he was outstanding in stretches), that he can score under defensive pressure (he hit a TON of threes with a hand in his face) and that he can score under mental pressure (he hit a number of big clutch shots). His defense is already elite, he can defend 3 positions, he can play two positions pretty comfortably, and he has a natural leadership ability that's pretty rare.
The best thing with smart is that aside from his defense, every other aspect of his game is in the 'room for improvement' category. His jumper isn't bad enough to be a lost cause, but isn't good enough to be dangerous - that means potential for improvement. Same with his ability to finish around the basket. Same with his passing, his ball handling and his rebounding. I think all those areas will improve with time, and that Smart will soon emerge as a Chauncey Billups type player - one of those guys who doesn't put up super-elite stats (albeit very good ones - maybe 17/6/5) but somehow creates winning atmosphere everywhere he goes.
I think Sully and Olynyk both have the POTENTIAL to be very good players.
Sully
Sully could be a 20/10 guy, but it's dependent on him losing the attitude issues and improving his professional work ethic. He has a high motor when he's on the court, but seems completely disinterested off the court.
His plus/minus stats and PER numbers are consistently solid, but he's held back defensively because of poor conditioning and offensively because he forces too many ill-advised jump shots rather than playing to his strengths (as a borderline elite inside finisher). If he could improve his conditioning and improve his shot selection he could be a borderline all-star, and could be that easily.
I'm actually not too concerned about his 3Pt percentages - he's got decent form on his shot, shoots a decent percentage from midrange and from the foul line - if he keeps shooting he will become a dependable 3PT shooter. What concerns me is that almost 1/4 (23% and 28%) of all his FGA were three's over the past two seasons, and that's far too much for a guy who is as skilled down low (and even from midrange) as he is. By comparison he has taken only 31% and 29% of his shots from inside 3 feet. Those two figures combined are a big reason why he has shot 43.9% and 42.7% from the field in the past two seasons, which is horrendous for a PF. The fact that so many of his shots (around 75%) have been jumpers is also a big reason why he had very poor free throw rates of 22% and 18% those two seasons...absolutely unacceptable for a 6'9" 260 lbs PF who thrives in the physical game (62% FG from inside 3 feet for his career).
By comparison in his rookie year he took only 2% of his shots from three and 45% of his shots came from inside 3 feet (where he shot an NBA elite 67%). The result? He shot a nice 49% from the field and had an at least somewhat respectable Free Throw Rate of 28%.
For Sully it's all mental - his entire career success depends entirely on his discipline.
Olynyk
I think Olynyk is quite possibly the most skilled player on the entire Celtics roster, who is unfortunately limited by physical attributes that he has no real control over.
Olynyk has everything - passing skills, ball handling skills, a great jump shot, good rebounding instincts, incredible basketball IQ (on both ends of the floor), decent mobility, a coachable mentality. He even has decent set of post moves, if his college career is anything to go off.
Unfortunately though, his combined lack of length (6'10" wingspan is vastly undersized for either the PF or C spot in the NBA), lack of physical strength (his frame seems to limit how much muscle he can add) and lack of explosive athleticism limits his ability to make the most of those skills. If Olynyk has a 4" longer wingpan, or another 20 lbs of muscle he could could probably be a beast in the low post. If he was more explosive, he could be an elite P&R finisher. Unfortunately for him though, he lacks both.
I love Olynyk as a player because I don't think there is a single guy on this team who makes the most of limited physical abilities the way KO does. Yet despite his lack of physical gifts, I still think he has a good amount of potential on his skills alone. If he continues to improve as a shooter and makes even small improvements to his physical abilities (added fitness / muscle) then he could be a dangerous support player.
His per 36 minute stats have been very good in both of his initial seasons, and his Defensive RPM stat (+1.71) indicate that he's actually a far better defensive player then people give him credit for. That number ranks him above Hassan Whiteside (+1.65), Dwight Howard (+1.58) and Bismack Biyombo (+1.59) and only a few slots below Robyn Lopez (+1.74), Al Horford (+1.74) Omer Asik (+1.85) and Marc Gasol (+1.92). Some pretty nice company there.
Zeller
Zeller I actually see as a dark horse - I think he has the potential to be a nice player one day. Not a great one, but a nice one.
Zeller has decent physical traits. He's 7'0", has passable (if not good) wingspan, has good speed and lateral quickness for a center, and seems to have good IQ. He's got a very nice touch around the basket (where he rarely misses), is developing a nice midrange jumper, is a good free throw shooter (and gets to the line at a passable rate) and is (IMO) a better passer than his assist numbers would suggest.
The main issue I see with zeller is that he sometimes struggles to score against length, but I think he could (in a couple of years) become a starting calibre center.
