Thanks for all the guidance from everyone, especially Joe! I have a few thoughts:
Joe, I misunderstood you on the Path. Yes, it ends in /public_html but there are other things in between. And I didn't need to do anything about Public Key Authentication or Passphrase.
I got one error message on the first publish for having two index files, one .html and the other .php. I published a couple more times with minor text changes and index.html never showed up again... must've been a default setting somewhere, but not on my project file, where I'd already set Default Extension to php.
Deleting index.html required getting into the site on BSH, and I first tried Transmit, but everything it showed on the site was just gobbledygook. So I tried ForkLift, and it was plain English, so I licensed it and got rid of Transmit. The two windows with Dropbox (where I store all my images locally) on the left and the site on the right should make for a really easy workflow.
I have an oddity that existed on my sites on the previous web host: on both the KC site I'm putting up now and the OG site (the big one) I'll be putting up soon, there's a paged named "resources." I don't know if this is a cPanel issue or a RW issue, but on the previous host's cPanel, it has the first resources folder handling all the resources sub-pages, then a resources folder inside with a folder structure inside matching the pages and sub-pages in which the images are warehoused. So the images for the Agrarian Urbanism page on the OG site, for example, are in public_html/resources/resources/initiatives/agrarian-urbanism. I'd love to keep this identical structure in BSH so I don't have to rebuild countless links to the images. I've already tried adding a resources folder inside the resources folder RW published for the page and its sub-pages, and there was no error message so I'm thinking that should work just fine.
Thoughts?