Noel has come surprisingly cheap thus far. Over his entire career, the biggest single-year salary that he has had was last year's 1/$5.0M contract with the Knicks. It doesn't really help him that he typically hasn't been a starter (last year and his first two years excepted) and that he doesn't play huge minutes and isn't a scoring threat.
The Knicks have $50M+ in cap space and are going to be throwing around some silly contracts this offseason, but somehow I think they're going to blow that money on big-name players and not Noel. They don't have even Early Bird rights on him, which means that they're going to be limited to offering $6M with non-Bird rights (probably a tad more than the room exception). We can comfortably offer more than that with our MLE without really breaking the bank. Honestly, depending on what our roster looks like (do we make any trades, who do we draft) it might not be a terrible move if we brought back Holmes with the Early Bird at about $11M (if he doesn't get a big offer elsewhere) AND signed Noel to something like $6.5-7M with our MLE to take the "Whiteside-but-we'll-actually-let-him-play" role.