Thank you all for your very interesting and thoughtful contributions. I've been debating internally over staining v non-staining, single bath v two bath, and sharpness v grain minimization. Caffenol is indeed an interesting option, since it is both a staining developer, and a low-toxicity one, too. I haven't used it much because it's awful to work with, in my opinion; black and horrible-smelling, long development times, and I didn't get very consistent results from it, so I never considered it very seriously. I wonder if it is a tanning developer? It has other disadvantages, too, like shelf life. Still, interesting.

I don't have time to respond appropriately to all the great contributions now, but I'll tponder overnight and try to post again tomorrow. Thank you all!