I'm giving this recipe 5 stars for the way it turned out after my modifications, without them I doubt it would have been as good. I took a lot of the previous suggestions, and I boiled my veggies in chicken broth (just added a boullion cube) although I didn't use peas (can't stand them) and just boneless, skinless breast meat. I used 3/4 cup of onion, and subbed 1/2 tsp garlic powder for celery seed (didn't have any). I drained the broth from the veggies, and used 2 cups in the pan, and after I added everything into the crust, I poured about another 1/4 cup of broth in with everything (as other reviewers complained it was too dry). Cooked for 30 min in a gas oven, and it came out perfect! Will definitely make again.
edited to add: I also made this with 3 small, cubed potatoes, and it made it even better.