Semi-synthetic opiates, I haven't tried any except heroin.
5meo-DMT, I've done N,N-DMT and loved it.
Ayuahsca, because I've done shrooms mixed with ground harmala seeds and that shit kicked my arse, and I've heard Ayuahsca is a little easier to handle.
Methamphetamine, Even though I'm not into stimulants I'd like to try once or a few times.
Ketamine, because my cat has done it but I haven't.
MXE, because my friends have had awesome experiences on it.
Mescaline, because I can make it and I'm not sure why I haven't. (In fact I'll be making some this weekend, a friend found some San Pedro's growing).
THC Acetate, because THC in a much stronger/pure form I've heard is extremely psychedelic like a short LSD trip.
I think that's about it. I sure love drugs ha ha.