One thing for sure, most would probably say (in hind-sight) "I wish we made it bigger". Once you consider the basic function for the pool (soaking, laps, exercise, games, etc) you can then pinpoint what is best for you (shape, size, and depth) and perhaps anticipate an average number of swimmers to expect. We have seating along one whole side of the pool and it's very nice. Large decking may not be required all around, but perhaps at least on one side to accomodate lounge chairs and such that take-up space quickly.