#2 High stakes

The last three King of the Ring tournaments were solely on TV, saved for an abrupt WWE Network special in 2015. They were won by William Regal, Sheamus, and Wade Barrett. See a theme? They all became "kings" and nothing else, probably because they were British (or Irish). There was no real implication of any of their victories.
Regal was set to do something interesting with his victory in 2008, but he got suspended soon after winning and therefore, the gimmick was scrapped
Sheamus entered a damaging losing streak heading into 2011 and Barrett would suffer a similar fate, before being gone less than a year after winning the tournament. This is a bad habit that WWE will have to drift away from.
Back in the 1990s, there usually was a championship match or at least a push in store for the winner. WWE should grant the winner a title shot at the next pay-per-view following the tournament, or perhaps even on SmackDown Live's debut on Fox depending on who wins. This would drive up the intensity and the excitement behind the entire tournament.