Thanks for the advice, everyone! Can I say again how much I love this forum? :)
Wax and other wax options would be great on a typical flat plastic or wood finish, but I would *not* attempt to put it on one of the vintage satin flame finishes - it can't possibly work on the bumpy surface, and there's no way to buff it which you need to do to make wax shiny. Your instincts are right - I wouldn't try it - it's hard enough to get dirt and other gunk out of satin flames (some say scrubbing bubbles works well, but I haven't found any really good cleaner yet).I just noticed that you said you're using new satin flame wrap - and my experience is all with the vintage wrap. Maybe the new stuff is made differently. Look at it up close using a magnifying loupe or strong magnifier - if it isn't a smooth surface (the old stuff is covered with bumps) then I can't see it working any better.
I've never seen vintage satin flame up close, but it sounds like mine is no different from the old stuff. It's about half as thick as pearl wrap, and it's not a smooth surface. It seems to be composed of thousands of tiny ridges -- I assume that's how it gets its 3D look. I assume that's also why it scratches so easily. It's beautiful wrap, but even though I'm babying it, I've already gotten a couple of nicks into it during the wrapping process. And this was supposed to be my gigging kit! DOH Depending on how well it wears, this kit may have to turn into a sparkle kit a few years down the road. :)
...Which is where the protection strategies come in. I like the idea of wrapping them in a clear plastic to protect the finish. I see Blick's sells a very thin clear acetate in 25" x 12' rolls -- $10 of this stuff would likely give me more than enough for my kit. I'll let everyone know how the experiment turns out!