Chris Singleton is an intriguing player for the Cavs to go after and would fill a big need and could contribute right away. Singleton may not have incredible upside, but he can come in and become a very good starter from day 1 at the Small Forward position. I think the guy is a little underrated by some, mostly because he didn't become a good shooter until this season but you can always improve your shooting (even Lebron was a bad shooter when he first came into the league).
Strengths: Chris Singleton is well-built. He is 6'9'' and a very solid 230 pounds, big enough to guard Power Forwards. He also has good athleticism, enough to guard some of the bigger guards. He has a good wingspan, a very good vertical leap, and enough strength to play the position effectively. He has the natural skills of a good rebounding SF. He is already a great defender which is what he is known for. He was the one that made the spectacular Florida State defense click. He is already a solid rebounder and has shown excellent offensive rebounding ability through college.
Weaknesses: He is not a shooter. He has developed his shot, but it is still at best a year or two away from being a true threat in the NBA. He is also still a very poor free throw shooter, shooting under 60% in his career for there. He is still very offensively raw in other ways. He is not a very good passer and never seems all that comfortable handling the ball. He also has very poor post skills at that point and bad footwork down low, settling mostly for catch-and-shoot situations. He has a very unnatural stroke and his shooting has been streaky.
Comparison, Best/Worst: a slower to develop Shawn Marion or Josh Smith/Trevor Ariza
Marion was much more developed when he came out at 21 and Josh Smith came straight out of High School. Things like post skills and shooting ability can be taught. The reason I compared him to Marion is the ugly shot, but he is more like Josh Smith. They have similar size, strength, and athleticism. Josh Smith didn't develop consistent scoring skills for a few years. Singleton will likely be at least as good on defense and with rebounding, though won't be as good of a passer. At his peak, I see a SF who scores 15/8 and plays lockdown D. He has the perimeter ability on D of an Ariza, but he can also intimidate people and block shots like Smith.
Why the Cavs should draft him: He can play lockdown D, he can develop his shot and he fits a position of need. The problem last year was injuries and if they can stay healthy and add a couple key pieces, this team could work its way into the playoffs.
Why the Cavs shouldn't draft him: He is probably a reach at 4. He also just had foot surgery so there is a chance that he may not play right away. There is also the issue that he may have limited upside.
Take: He probably would be a reach at #4, but if the Cavs like him and grab him, I would not complain. After Irving, to me the rest of the guys just depend on your preference of player. If the Cavs trade down, he is a definite player to go after with a lower lottery pick, just probably not this high.