Summary
Niang really has one job - make open threes. The percentage of Niang's shots coming from beyond the arc have gradually increased each of the last three seasons as the Jazz overall have ramped up their attempts, as 73% of Niang's shot attempts this past season were three pointers. Niang makes these shots at a very good clip - as he's a career 42% three point shooter, and hit 44% this past season. Niang has quickened his release, which allows him to get more shots off and overall be a more effective threat as a shooter. He's still someone that defenses are happy to run off the three-point line, but he can at least make a couple dribbles and make a play when defenses completely sell out to stop the three.

On defense, Niang is pretty slow-footed, so defending on the perimeter is difficult for him. He's also not big enough to really battle inside or be any sort of rim protector. Because of his limitations outside of his shooting, he's probably not someone you want to trust with serious playoff minutes, and did not have a good playoffs for the Jazz.
 
Cap Considerations
Niang will be an unrestricted free agent with a $1.7 million cap hold and full Bird Rights, meaning the Jazz will have no restrictions on re-signing him. However, re-signing Niang to anything above the minimum could be costly for the Jazz, especially if they re-sign Mike Conley or make other moves that push them into the luxury tax.

Other teams will have multiple ways to sign Niang as even teams without cap space could possibly use any of the Non-Taxpayer MLE, Taxpayer MLE, or possibly even the Room MLE or Bi-Annual Exception to sign him. There's also a chance that Niang ends up settling for the minimum.