Drugs are bad for you, m'kay.
Wrong website for this, Bluelight is about acknowledging that abstinence-only drug education causes more harm than good, so we're here to openly discuss harm reduction as far as drug use goes.
On the topic of the thread, there are an ENORMOUS amount of Z-drug scaffolds, and most of them are not insanely difficult to make, but they're far from simple. On top of that, Z-drugs are not very popular on the market, and they're known for causing potentially dangerous adverse behavioral effects. People acting a fool, essentially. Pagoclone is a good example of a Z-drug that was on the black market within the last few years, it was marketed as a less sedative, more hallucinogenic variant of Zolpidem (brand name is Ambien). As a huge fan of Ambien, I wanted to grab some but the cost relative to dose ratio was enough to sway me away from acquiring any. I could easily see market factors being the reason that these are not more explored, but I personally know of a Canadian chemist who has whipped up ~50 variants of Z-drugs in the last few years. He told me that they were the worst selling compounds he's ever listed on his marketplace website. He claimed he made most of them just to explore the SAR, and he found a ton of fascinating hallucinogens, kind of a Shulgin of the Z-drug world in a way but only working off of 2-3 separate scaffolds, whereas Shulgin technically worked in a variety of scaffolds if you include things like his work with benzofurans (F-2 & F-22), 2C-G and its amphetamine-like homolog G-N which are based around naphthalene iirc, other bicyclic 2C-G's, MEDA (super whacked out structure), and beta-carbolines like harmaline. Later on people like Trachsel studied and wrote on COUNTLESS other psychedelic scaffolds, I can't wait for an English translation of that book because my German is mad rusty rn.
Edit: How did I forget to call out Nichols, and of course there are countless other psychedelic synthesists out there further exploring the domain of hallucinogens. I personally hope to encounter more kappa agonists in the future, as a salvia enthusiast I'd love to see what else that receptor has to offer.