Lith seem fun to me, not necessarily good . There's a lot of other stuff I would like to control better before I move into the far reaches of esoterica; like developing for contrast control or split developing.
I've also got a 10 year old set of Colorvir toners sitting in my darkroom, I'll get around to playing with it if I feel adventurous one day.
I also mix my own chemicals - lots of funny smells that way!
Pyro? Weeeeelll... I started playing with Pyrocat-HD. That's fun enough for me. At present. But it doesn't really help me with my 400g surplus of pyrocat...