If I'm not mistaken, the JW Marriott is the nicest of the three in Downtown Los Angeles. And although I have never stayed at any of those hotels, I am very familiar with the area and am commenting on logistics. Some may disagree, but I do not consider Angel City and any of those hotels to be walking distance. You are looking at 30 minutes plus of walking. The Ace Hotel to the Bonaventure or Sheraton Grand is doable, though. I really like the Ace Hotel and Angel City, so it sounds like a blast!