Challah really sucks up the flavor for some reason. I'd definitely add more stock
(definitely not low-sodium) with some coarse ground pepper and additional sage, marjoram and thyme (or poultry seasoning) stirred into the stock before mixing it into the stuffing. You need the stock to help distribute the spices/herbs evenly through the stuffing, but don't use so much that the stuffing turns into bread soup, and mix it all together with a light hand.

Just before serving, sprinkle it lightly with a good coarse salt.

i would definetely go with adding sausage i wouldn't go without sausage or apple along with the afore mentioned aromatics in my stuffing. if you cant have pork theres always veal , turkey, or chicken sausage its the spices in the sausage that give a nice flavor

I don't have a suggestion to share - only that reading about your stuffing and seeing everyone's suggestions makes me want to swan-dive headfirst into said stuffing. :) Sounds delicious.. hope it comes out great.

I love this website! It is amazing how many people responded so quickly! I feel greatly supported in my food endeavor! Wow! Thanks everyone!

Mushrooms might help as well, either roasted/sauteed or reconstituted dried mushrooms, chopped and stirred through. Or a shower of grated parmesan on top!

Since you used chicken broth, I guess it's not vegetarian. In that case consider some sausage or bacon.

Try a bouillon cube to liven the stock (if it's not homemade and you're adding more) also, maybe some apples, or sausage? It may also taste better tomorrow after having the flavors meld tonight.

I agree with drbabs, increase your aromatics. In addition consider adding some sauteed cubes of apple, caramelized onions, or toasted nuts. I am assuming you are keeping this vegetarian, but you could add some soyrizo or other vegetarian sausage as well.

I agree. Sounds like you just need to add more of everything.

More onions, garlic, sage, salt and pepper. More herbs--maybe thyme and rosemary. Saute some mushrooms in butter and stir them in.