The ultimate RV Resort would have sites parallel to the lake with concrete pads large enough to accomodate up to a 45ft RV plus one extra vehicle. On the lake side of the pad there would be room for slideouts plus pinic table (nice sized patio area). There would be 20 feet separation between each site with trees and hedges.
That being written, you design the park to give you the most bang for your buck. Make sure you add the usual amenities, laundry, restrooms with showers, swimming area, clubhouse, store/office, playground, pet stop...etc. Really good high speed WiFi with lots of bandwidth even for a small fee is very important. If it's nice, well maintained and in a popular area, RV'ers will flock to it no matter how close the spaces are.
