Kiteena,
Wow, you must be bursting with joy to be able to plan a last minute vacation just weeks away. It will be here before you can say "supercalifragilisticexpialidocious"!
I will give you my honest opinion, I personally think you should pass on the Deluxe or Premium Dining Plans since you may not be able to use them to the fullest. This doesn't mean that you still can't dine in some great places. Don't be discouraged and keep calling or checking online for advanced dining reservations for the places you would like to dine. Cancellations happen every day and you never know when pixie-dust might be floating your way and you might be able to snag a perfect reservation!
Keep in mind that
Be Our Guest Restaurant does offer a quick service lunch option that doesn't require a dining reservation. A line will begin to form rather early, but it might be worth it for your little princess to dine in Beast's Castle. Another fun option that doesn't take reservations is
Beaches & Cream Soda Shop at Disney's Beach Club Resort. It is one of my personal favorite dining locations. It might be fun to take a boat over one late afternoon from Epcot and indulge in an early dinner with a special ice cream treat afterwards.
Again, the decision is ultimately up to you and you should base it on your personal expectations and budget! I hope your little girl has the most magical trip and the memories are overflowing with pixie-dust!
~Allison L