@Paulaenos I'm impressed! That is really disciplined of you to go through and systematically make all soaps in the books!
I got some books from the library. I read them but as far as making the soaps, most of them didn't speak to me. Plus, I've been trying to stick to one recipe and only making small changes as I try different fragrances, colorants, exfoliants, etc. Otherwise, if I mess it up, I won't know how to figure out what went wrong.
If you were comfortable not working from a book, you could think of the property/ characteristic that you think you'd like in soap. So, would it be the color or the scent or property (like calming). Then google around and see what spice, clay, flower, herb or essential oil would get you there.
I assume Jan Berry's books have more than is on her Nerdy Wife website. But, she has information about natural colorants. Tanya Anderson's, Lovely Greens website has a ton of information about natural colorants.'
Good luck find a resource that you really like!