With such a long drive, I would consider staying at least 4 or 5 nights in a hotel, not just three. That way you can take advantage of the multiple-day tickets you'll be paying for. Like aztecgoods suggested, perhaps a nearby offsite hotel would be a better bargain and you could take advantage of more nights for the same price or less.
I don't know anything about the new meal plan, so not sure if it would be a good deal for your group, but I would guess your age group could consume sufficient quantities of food to get your money's worth with it.
But I would suggest you read some of the reviews here from people who have actually done it to see if it sounds like a reasonable option.
Susan
I don't know anything about the new meal plan, so not sure if it would be a good deal for your group, but I would guess your age group could consume sufficient quantities of food to get your money's worth with it.

Susan