Pointing to guys like Whiteside, IT, and Crowder is nice, but I think the best bang for buck is always going to be superstars, who get paid far below what their value would be in a truly open market.
Top players in the NBA -- Curry, Durant, Kawhi, LeBron, Westbrook, Harden etc. -- would be worth 40-50 million at least with no cap.
Curry and Harden make the least out of those guys.