We have an above ground pool. It's about 5 feet tall, and I think the diameter is about 19 feet? It requires a ladder to enter and exit, and the ladder is removable. The small kids can't even come close to climbing it (the frame doesn't allow for climbing) and the big kids are trained that if they even look at it without my approval, they sit for the afternoon, LoL. When it's not in use, the ladder is placed about 6 feet away, and even my almost 11 year old can't get it into the pool without adult assistance. I understand that some parents may be turned off by it, but I take all the precautions that are necessary.
If we are using the pool, I get the okay from parents in advance, and my hubby is usually the one who takes them in, one at a time. I also have a sister-in-law who is a lifeguard. That helps, because she'll come over and give me a hand sometimes.
I do tend to stick with the little baby pools, emptied daily, and splash mats/sprinklers. Just easier.