Bumbershoot
Like you I am an uberplanner when it comes to Dinsey vacations. We did WDW after two trips to DL as a warm up. I too was overwhelmed by planning. It was one of the reasons we didn't do it earlier! The dining plan was awesome!
I did notice at all of our meals, there were vegan options. We ttried to do as many character meals as possible because the lines for autographs were impossibly long and the amount of time they were there was very short. PM me if you have any questions