This is a build i had in mind for long time and did it on a server I was playing back few months ago
Swimming pool that actually helps you level the swim stats,
in order to make this the only struggle is to find a good small island create around it, then wait for storm in order for the waves to let u dig as deep as u can
Also for the good looks I've added a spa deluxe with some bathtubs to chill after reaching 100 on swim and jumping pads with difficulty levels ahaha