I am intrigued by this picture. Since you will be felling trees, one of which is probably rotten in the center, could you build something like this with your own wood? Then you could grow moss on them? Would it be possible to attach a basin of some sort at the end of each log? Aimed at an angle that when full, it would spill into the next log? Or a succession of basins, so there could be three individual birdbaths in the picture?
Is that (more or less) what you said here?
I though about a tier with maybe 3-5 bird bath type areas where the bottom bath has a float switch activating a fill from the top which will then spill downward until the float switch stops it.
Now,
that... you could sell to Becky!!!
You are thrifty, using your own logs to make it. You will have an outside source of water for the birds, and the bees, and the cats. The sound of falling water is very soothing, so it would make a nice spot for relaxing.