It's tough to get value on long term deals. Once a guy hits year 5, often,, their skills don't match their salaries. No doubt that EK is an exceptional player, but he's suffered some serious injuries which, unfortunately, may have consequences on his long-term play. A simple rule for investing is to buy low and sell high and EK's value probably won't get any higher. The challenge for PD is guessing what move will benefit the team most. Trading EK will only make sense if he hits a home run. The fan base will run him out of town if the return us anything less.
Keeping EK, at the right price, makes sense too as he is the face of the franchise and is respected in the community as well as the dressing room. Guys like him don't come around very often.