... theme at a whim I would like 
I think the closest you'd get to that would be to use the def icons. It wouldn't be hard to create several different directories with themed def icons and then write a little script to run on startup that would let you pick which theme to copy to ENV: The only problem is that you'd have to delete most/all of your real icons for this to work and set the drawers ti display all files and not just file that have icons. The REALLY big negative to this is that you'd have very generic icons for everything and would have to go only by the filename to figure out what each file/drawer is. For example, there'd be no way to visually distinguish the "Prefs" drawer from the "Utilities" drawer or even the "Devs" drawer. Personally, I don't think it would be worth it.
