@firemist These might be some odd suggestions, but most of the obvious stuff has already been said.
First, you might be doing too much high-intensity work. It gets a lot of hype, and "science says" and whatnot, but you should probably work on more zone 2 cardio in sessions from 45 minutes to 2 hours, combining it with stuff like thinking, chatting, or watching movies to make it feel like you're doing something, and drop some of the intense stuff. It could be that you're wearing yourself out on a metabolic level... or something. High intensity should always be balanced out by low intensity.
Add more vegetables to your diet. Get a variety of whatever tastes good, and just cram lots of them in to stop yourself from feeling hungry. You won't need as much discipline, though maybe it won't matter much if you try the "reverse dieting" approach. That sounds fine to me too.
Protein probably doesn't matter. You say that you already have a lot of muscle, so more protein would just be more calories and more satiety. It'll be no different from getting those any other way, since your body already has access to that protein.
Make sure to drink plenty of water. If some of that fat is actually water weight, then drinking lots of water will reduce your tendency to retain the water.
Get your iodine and all that stuff...
That's all I have right now.