freeland,
You will be visiting DIsney during the absolute peak attendance period. You
absolutely must make more ADR's.
The Deluxe Dining Plan only holds value if you eat all or almost all table service meals. If you eat at very many quick service locations you will be losing money, and you'd be far better off to cancel the plan and pay out of pocket.
Because the time you are traveling is so incredibly busy, restaurants will be booked. (They are often booked in much less busy times of year) If you do not have dining reservations in advance you will be highly unlikely to find a seating available.
Honestly, I wish I could give you a different answer, but there really isn't any way to make reservations without planning around them in advance. My best suggestion would be to visit the
Parks Calendar page and determine which park you will be in for each day of your trip. That will help you to plan your meals around the park's hours and parade/show times, so you don't miss anything important.
Finally, if the planning does not sound like something you are interested in doing, I strongly encourage you to downgrade to the basic dining plan. You can still pay out of pocket for additional meals if need be, but at least on the basic plan you won't be losing money when you eat at quick service locations.
Best of luck!