What about if you think of total time spent doing each activity.
In this case, getting in and out would be the activity that would have the least amount of time spent on it. Lounging, sitting, playing, exercising, soaking, floating, all of these activities will have more total time spent on them than the total time it takes to ingress/egress.
That's an important consideration, for sure. I would counter with... of all the things you can or will do in your pool, what are the two things that you, and every other person that uses your pool, is going to do
every single time? Get in, and get out.
So let's go about this from another angle. Let's take soaking, floating, lounging off the list. None of those will be affected by step or bench placement.
The bench doesn't affect the swim lane, neither would the steps, as you or I have imagined them. So that can come off. As can general playing in the pool.
I think this comes down to volleyball, sitting, and the steps, yes? Did I leave anything out?
I'm still thinking comfortable entry/exit (not jumping in, or climbing out) is going to necessitate a set of steps on at least one end of your pool or the other, not in the middle as you have them. The shelf end is the logical one. But I also still think you're going to make good use of steps leading to the spa. I'm just stuck there, I guess, steps on both ends, not in the middle. Getting in and out of the pool should not require a walk across a bench. I'm stuck on that, too.
So, what it comes down to, if you're following that logic: a bench or benches that start after the steps end, and there is either one long bench that spans the middle (to accommodate the max number of seats), or one that breaks in the middle to accommodate play at the net). My choice would be the latter, because, as I said, I don't think you need all that much bench. Remember, you have lots of lounge area on the shelf, and along the shelf, and in the spa. So unless you've got dozens of people, a lot of the time, half of which need to be sitting down all the time, I'm not too worried about places to sit.
The only other idea I've come up with: the bench runs the whole length of the pool, with or without the middle cut out, and there is a small step below the bench, one on each end, that would get people up on the bench. My bench only needs one step below it. Those two steps would encroach a bit into the swim lane, and into the "volleyball court," but not enough, I think, to really impact either activity. Then from the bench there would be another step to get out. Again, one on each end. Maybe the shelf would be the step out on the shelf end.
I don't have your pool's depth profile, or length or width, handy to give you any meaningful numbers, so you'd have to play around on some graph paper.
I would do just that. Draw your shell and spa and shelf on a piece of graph paper (the things that are in stone), and copy that a dozen times. Then just start drawing in all kinds of versions of steps and benches. Don't over think it, just get a lot of ideas down on paper. I use this trick a lot while designing. I'm not really after the final solution, it's a brain dump. Often times, something will emerge, or be inspired, during such an exercise that wouldn't have with any other process.
Post your contenders here, and we'll go from there.
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