Your discussion made me realize that although I was imagining a permanently visible menu, it would be quite alright — and maybe better — to have the menu popup on a keystroke. See Reveal Safari Windows. Something like that macro’s popup would be sufficient, as long as I could dynamically add to and remove from the palette it presents. I don’t really need it to be permanently visible.
By the way, I think I am going to change that macro. The way it works is that if it asked for a string with a slash, it looks at URLs, otherwise it looks at window titles. I have run into enough windows with content titles that don’t include the name of the site or top-level starting point, where I am starting to think i should check URLs even if the string doesn’t have one. (An example: the window title “Document” in the documentation pages for a NoSQL database that doesn’t include the name of the database in the title)