I think you can make it work with a DP. There are enough choices to make it happen if you are careful about which places you visit to eat. You can also work with Disney's special diets department if you have special needs. Also, buffet places allow you to pick what you eat; so, you can control what you eat. You can even get a supervisor at the buffet places to walk you through the food; so, you make the best choices. You may have to wait a little longer to get a supervisor to help, but it's doable.
You didn't explain the mix in your family, but sometimes even if you feel you are not getting full value the other members in your group make up for your lost on the dining plan.
You can certainly do out of pocket, too. I would play with menus and costs and see what would work out best for you. I think the dining experience is part of the fun at Disney.