Interesting and unexpected responses. Good to know. Unfortunately, I didn't have much in the way of blue skies during the week I was there, so I wasn't able to get the dark IR skies with pale clouds I would have liked. My camera is IR-only, not a visible-light-too version, so the comments about additional filters don't really apply; I think I just took pictures that presented themselves to me and weren't differently dramatic in IR, instead of searching for situations that *were* dramatically different in IR. (The vast majority of the images I took were regular color ones; the IR was an occasional diversion.)
I took color images of the same (or very similar scenes), and I've attached them for comparison. For the first, the IR makes the foliage pale and the reflection much stronger. For the second, the orange portions of the gateway were much paler in IR, setting them off from the black cross-pieces, which I liked (and, again, the pale foliage is a bit interesting).
I'm aware of techiques for fabricating weird-looking science-fictiony false-color images, but am not particularly interested. I prefer the more natural (in some sense of the word) and subtle look of B&W. (Though from your comments, maybe it's TOO subtle...) I'm not trying to produce images that scream "gimmick! gimmick!", but pretty images to complement what I do in color. I'll take a look at the false-color links, though, and maybe play with it a bit ; thank you for them.
Most of the time, I just desaturate the image in ACR. I've made a couple of attempts at bringing the image into PS with the individual color channels still intact, and using the channel mixer to create a gray-scale image, but am still experimenting to get it to do something reasonable.
And thanks for the kind words, Peter.
Forgetting about any IR issues, are there any B&W photogs out there who can comment on how they might adjust the tonalities of these images differently? (Oldcsar: when you say "originals", do you mean the RAW files? Not enough bandwidth. Or do you mean downloadable versions of my final images? You can click on the thumbnails and then right click and do "save as" to save a copy.)