Do you think having a lip in the floor going into the sitting area so the pool cleaner does get up into ?
I know it's easy enough to block a cleaner. My pool drains were creating havoc with mine, so the right lip or step will solve for that, for sure. Two issues come to mind:
1.
You're creating a manual-clean area. Most pools have them to some degree: steps, benches, sun decks, etc. So most of us have to do a little manual brushing. The question then becomes: how much are you going to be willing to do? How bad is your debris problem? Lots of leaves? Twigs? Bugs? Or none? Think that through.
2.
Depending on what you're describing, you might be creating a tripping/stubbing problem. You can mark it, so people will see it. That's what those little tile insets are for on steps. But imagine: even a light wind, or people splashing around, will break up the surface enough to obscure what's under water. When that's a top step, no big deal. Three feet down and the bottom can be almost totally obscured. Plus, there's refraction. What you're seeing from above the water line is not exactly where it is. It'll be some inches away, the deeper it is, the farther away it'll be from what you think you're looking at. Add to that a little libation, some water or sun in the eyes, and "Doh!" there goes your guest's big toe! I'm not sure how far fetched that is, but I think it's entirely possible. People expect steps to be where they usually are. A big underwater shelf three feet down across the middle of a swimming pool... not so much.
I keep coming back to the same thing. There are legitimate reasons you really want to have something permanent and necessary in your pool. Like steps. And lesser reasons for less than necessary things: like benches. Farther down the list (for me) are sun decks. (I just don't get 'em.) All these things encroach on where you can play and swim. And what your cleaner can reach. All trade offs. Are they worth it? For me, personally, a permanent table would be way down the list, even though I can imagine how cool that would be (once in a while). But it sounds like my family and I use a pool differently than what you might be wanting to do with yours. My kids would be jumping off that thing and thrashing and spilling anything I put on it. And maybe you're OK with a little extra brushing of your pool. Maybe you'll get better use out of that area of your pool by sitting at a table in it instead of swimming in it. That's totally cool. That's the great thing about designing your own pool, you can have it your way. Oh, and I should point out, I have a fairly small pool, I couldn't afford the real estate. If you're building a giant pool, then yah, table, benches, beaches, sky's the limit!
But I'll throw one more idea at'cha. The Sunroof Paradox! (I just made that up, but I'm hoping it'll catch on.) For decades I pined for a sunroof in my car. Reeeeally wanted one. Thought it would be fantastic. Wind in my hair. Sun in my face. Fantastic!! For one reason or another, it just never happened. Until... my latest car, I could finally afford to order one new, custom. First on the list: a sunroof! Finally, fulfilled!
I've used it twice. Hated it both times. Wind in my face. Sun in my eyes. Over it. Point is, something might sound like a great idea, until reality intervenes. For me, the sunroof realization was not a biggie, I closed it, drew the shade, never been an issue since. But a permanent fixture in a pool's plaster is something else. So I'm not trying to talk you out of your table, at all, just trying to talk you into leaving yourself a way out should you later realize it's not worth the possible negatives myself and others have been describing. I think you can have both: the table you want, but without compromising the floor of your pool so much that you're stuck with this decision forever, if it later loses its appeal...
