Well, you have two games (Rizar's gate and Stalfolia) already in progress, that you're stopping to make this, cutting out almost the entire point of the water temple, using water levels to float/sink you to solve problems, and adding an ice temple while that was the purpose of the ice cavern. I honestly don't think people see everything that they'll have to do to make an OoT remake.
All of the time travelling stuff is difficult, such as the shadow temple/bottom of the well stuff.