Nitrous Oxide is a useful tool for psychedelic exploration. I find that it opens the spiritual door, but doesn't quite reach into the areas of challenging emotional material like a major psychedelic. So that can be nice. However, I think ultimately you get more growth by becoming comfortable with that emotional material. Anyway, I wanted to add that methionine may be a useful supplement for use with N2O. That angle may be covered with a B12 supplement, but I figure you want to be as safe as you can. Relevant articles have been updated.
Nitrous Oxide Brands now links to these.
Piracetam may be useful by itself for meditation, seemingly increasing alertness and present moment awareness. And it seems to be useful in combination with psilocybin, increasing the effects (yes) while simultaneously keeping one a bit more present (maybe). But I've been using all this stuff at pretty low doses mostly, and I notice that for myself, as I occasionally get up to 2-3 grams of mushrooms in combination with piracetam (note: perhaps the equivalent of 4-6-9 grams of mushrooms by themselves), it's just feeling like a bit much, a bit strained. Which it probably is. My point would be that with mushrooms alone, a high dose trip seems substantially more comfortable. So for the low dose kind of stuff I do, maybe up to 1.0 gram of mushrooms, it's okay, but beyond that, if I wanted to go big, I think I'd lay off the piracetam for a while.