Summary
Known more as a combo guard when he entered the league, Rivers has now established himself as a full-time wing. Rivers has played a role on good teams in Los Angeles, Houston, and now Denver, where he can spotup around elite playmakers and be a secondary playmaker when necessary.

Because he has the ability to break defenders down off the dribble, he has value on second units that struggle to score. When the shot clock is winding down and the normal flow of offense hasn't created a good look, it's nice to have somebody that can create something decent. Rivers is not somebody that you want handling the ball too much, because he has never been that efficient of a scorer, nor has he been one to use his isolation ability to create good looks for others. However, Rivers can certainly provide value to winning teams if he is in the right role.
 
Cap Considerations
Rivers will be an unrestricted free agent with a $1.7 million cap hold and Non-Bird Rights. This means that the highest starting salary the Nuggets could offer him using the Non-Bird Exception is $2.9 million. This should be enough to retain Rivers, since he settled for the minimum to come to Denver after agreeing to a buyout with the Knicks. Alternatively, the Nuggets could use their Mid-Level Exception to re-sign Rivers if he demands more than $2.9 million.

Other teams will have multiple ways to sign Rivers 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 he signs for the minimum.