Since you mentioned you're vegetarian, I thought I'd chime in on my experience with the two places you've listed that I've been to.
CRT was fantastic. We went in August and the vegetarian option was a Tofu Vegetable Couscous (looks like it's currently the same) and it was absolutely delicious. For an app, I had tomato soup, which was also very flavorful, though your app option may vary. 2 credits is a lot and the value on the DDP isn't the greatest, I felt it was totally worth it. It was our favorite restaurant of the trip.
HDD- I know you said you cancelled it, but thought you'd like another perspective. They have a separate vegetarian menu with 3 options. 1) Pasta with butter, oil, or marinara, 2) Grilled Veggies in Vinaigrette (squash, mushrooms, zucchini, and tomatoes with spinach and edamame), or 3) Pasta Primavera with veggies and marinara sauce. There's also a Grilled Salmon with veggies option if you're pescatarian. I went with option 3. It was simple wagon wheel pasta with marinara and vegetables but still good. Vegetarians are also provided with the salad, cornbread, mashed potatoes, corn, and strawberry shortcake from the regular menu. In my opinion, it was a ton of different things to eat (far more than I'm offered as a meal at most restaurants in Disney or elsewhere) and definitely didn't feel like I had to scrape together a bunch of randomness to make a meal. (I'm used to making meals at restaurants out of random sides and I know it sucks.)
Anyway, again when it comes to the 2 credit value on the DDP for HDD, it's not the greatest, but the experience itself of HDD definitely was. The fact that you get a show along with your AYCTE dinner, plus unlimited alcohol and tip included lessened the blow of spending two credits.
Everyone has different opinions, but CRT and HDD are now on our repeat list for our next trip.