SecretMe,
You are on the right track. However, what seems important to one person can be different from the next. In addition to the resorts theme, you would want to consider location, on or off property, how old is the resort, size of rooms and their layouts, the rooms' decor. Maybe you value the range of recreational activities offered...pools, hot tubs, golf course, gyms or recreational rooms.
It's important to me that there are good places to eat nearby, if not in the resort. And my grandkids want to be close to their favorite park. I'm not really wild about huge resorts either.
Check the annual maintenance fees to see which is lowest. Be sure how many years are left on the sellers contract. And consult a points chart so you'll know what's required to book a certain accommodation at any of the resorts. Hope that gives you some food for thought.
Good luck finding your perfect family vacation plan on the resale market!