You are correct that you dont want a handicapped room unless she needs the features of the accessible room. People assume they are close to everything, but they are actually spread out all over each resort. So, no more likely to be close to the main area than any other rooms.
I would suggest not requesting a specific room because chances are good that room may not be available - and with 2 rooms, they may give you that particular room, but not have another close by.
What is most important to you to be close to? The main area, buses, pool?
I would suggest requesting close to that, whatever it is and making that your first request.
If both rooms are on 2 separate reservations, make sure you link them so that they know you a traveling together.
With the
ECV, she will be able to get all over the resort, so location may not be as important as you are thinking.