Having played just five games in the D-League since the Washington Wizards assigned him and still making his way into the rotation as just 19 minutes per game off the bench, it's tough to evaluate N'Diaye beyond what we've already seen from him in college and at Portsmouth.
The best thing to take away from the limited action we saw from N'Diaye is the physical and vocal style he brings to the defensive end, doing a great job communicating with his teammates, stepping out to help on the perimeter in the lane, and really asserting his physical tools well all over the floor. He did a decent job when matched against Cole Aldrich in one game, bodying him up well and doing a solid job keeping him from establishing dominant position. His ability to block shots both in the post and helping from the weakside is a great strength, but cutting down on his fouls needs to be a priority.
Offensively, N'Diaye is still very much a work in progress, not being able to contribute much other than an occasional jump hook in the post and hitting just a poor 4-for-15 field goal attempts in his five games since being sent down. Finding better ways to impact the game off the ball should be his priority by getting open on cuts, pinning his man under the rim, crashing the offensive glass, and setting hard picks to get teammates open, as his post game is still very much a work in progress.
Looking forward, N'Diaye still has some work to do, but getting some minutes in the D-League should be pretty good for his development. Cutting down on the fouls and finding ways to contribute offensively should be his main priorities, while further developing his post game or becoming a more respectable mid-range shooter wouldn't hurt either.
N'Diaye is doing a nice job of showing teams what his role could be at the NBA level, as his combination of size, length, strength and toughness is difficult to come by, and the fact that he reportedly has outstanding intangibles will help him quite a bit in his goal of sticking around long-term.