I see you have put a lot of thought into this, but its not just about finding sleeping areas for everyone. One of the best pieces of advice I have seen here for families considering full timing is to think about what it would be like with all of you stuck inside the RV for several days at a time in inclement weather. Because rain happens. Pack up your kids and go to an RV dealer, load them all into any RV and see how it feels to actually have everyone inside. I don't know if you've done any RVing with the kids yet, but if not try renting one for a week and see how that goes. Act like its raining outside the whole week, and keep everyone inside all day every day.
This will also help to consider where you will put everyone's stuff. Kids go through clothes, a lot of clothes. How will you do laundry? How often? You can get buy with just a few outfits each, but then you will be buying new outfits more often as they will wear out faster with so frequent washings. Also, consider the seasons, warm summer type shorts to chilly cool weather coats. You will have to carry it all with you. And yes, you will also need warm clothes in Florida at times.
You really should do all this before you sell your house, because you wont have a lot of time afterwards, and some people take a very long time just finding a good RV. And, once you've found one, you will also need time to do the remodeling and then move your stuff into it.