Lol the Ganon fight was terrible from start to finish. If felt so anticlimactic, especially the final phase with the giant beast. I also remember farming dragon horns to stock up on the mighty dishes for the big attack boost, only to find I didn't need them at all. It was definitely more challenging the second time around fighting him without completing the divine beasts first, but yeah, would've been better if beating them provided some other kind of buff. I never finished the game in master mode (last I remember I was struggling to beat the rogue shrine monk or whatever from the DLC), so I'm not sure if the regenerative health thing made it any more difficult.