i sprout wheat, sunflowers, barley and lentils for the
rabbits (and for me).
Buckwheat every once in awhile too, although I find that buckwheat takes longer and has more mold issues. Flax is similar.
I would think there is probably not a huge variation in nutrition among different kinds of sprouts and I would probably go with what is cheapest (like two significantly different kinds, probably sunflower and hulled barley, probably. Pearl barley, I don`t know if that will make a sprout?)
Beans, I am not sure about toxicity. The famous baddies are kidney beans, but I`m not 100% sure that sprouted beans or chickpeas are okay without being cooked (I`m not a vet or a
chicken expert, but I know for human consumption sprouted beans are a danger zone. Lentils, on the other hand, are fine, and are a regular feature in my own human diet....)