I'm gonna toss a dark horse suggestion into the mix - LA. I know people will point to them and say it doesn't fit the criteria of currently competitive, but they have a high quality, deep prospect pool that's about to add one of Stutzle/Byfield. They have 2 pillars in Kopitar and Doughty that - despite wearing some mileage - are still capable of high end/elite play and were leaders for two championship runs. Another thing they have is ample cap space. Only 2 long term contracts in Kopitar and Doughty, 17 mil in available space currently, with another 5 likely available in the form of a Carter trade (where this year plenty of teams would gladly take a 5.2 mil hit that only makes 2 mil in real dollars).
It's not necessarily the roster you see today that your signing to join. With all the space the Kings have moving forward, along with the strong prospect pool and appeal of playing in a world class city, I could see them as a possibility for a number of UFA's.