The quiche has a small side salad on the plate, only menu item that has a salad. It's not a separate item so can't be subbed on another entree.
I second the green beans as a choice, they are slightly crunchy and really good. DH hates anything green, but liked them instead of fries too. So many plates around the parks come with fries, he just wanted something different.
When you pre-order, as you pick each menu item it will give you what choices there are for changing out fries, no sauce, etc. These are the only modifications you can make. There is also a link for allergy ordering, but looks like it just deletes menu items that would have an offending ingredient. I didn't explore that feature very far.
I was able to switch my dessert for a french onion soup this week, even on pre-order. For the
DDP they will ring it in as a dessert, then call the kitchen to change the dessert to the soup. If the kitchen is busy, I was told they might not get the message in time before your order goes out, and if the soup did not come just alert the server of the change and they'll take back the dessert and bring the soup. This did happen to me, just had to wait a few minutes for the soup.