I am curious as what other developers you Caffenol folks use, and why.

As whole, or as add-on to a Caffenol mix?

FWIW, I'm using D-23 as a baseline. It was Kodak's planned replacement for D-76 long ago and is fairly similar, cheap and easy. Two ingredients. Guess it didn't catch on that well, cause D-76 remains the industry standard. Times are billed as similar to D-76, but YMMV.... as mine has ( a tad longer ). I've always liked Ilford's Perceptol which is chemically similar, but paid an ISO speed price. Now that I'm shooting 4X5 from a tripod, speed is kind of irrelevant. Good to have a standard developer of some sort in your belt. D-23 can also serve as the basis of DD-23 which converts to a two-bath. Thought I'd mess with this some time back when I was reading books, but if I don't have to, so much the better.

I’ve seen a recipe for ‘teaol’ but not tried it yet. Instead of coffee it uses green tea extract which has a stronger reducing agent and therefore creates less contrast