1. Price
A lot of this is determined by players. Currently I think everyone is paying too much for most drugs from a gameplay perspective, but it makes enough sense RPwise. I think lowbies and nobodies should still have access to drugs, even if they are priced out of the best or rarest ones.
2. Duration of effects
I don't think any recreational drug should last under half an hour. If they followed their IRL counterparts we'd be looking at 40 minutes for weed, 4 hours for endo and dez, 8 hours for the hallucinogens.
This could make them kind of an amusing value proposition. Taking LnA-3z at a party and then having to talk to a Judge or your boss because an emergency comes up is really very funny. It's also important because scenes in Sindome tend to be pretty long and it's weird sobering up five minutes after smoking a bowl. I understand there are some activities you don't want people walking around with forever buffs for, but drugs come with enough drawbacks that I don't think it's the biggest problem in the world.
3. Stacking
This seems fine. I think stacking drugs of the same type should come with diminishing returns, and I think there should be some kind of reasonable cap on how much you can boost your stats overall.
I think you should have a sense of how fucked up you are, even if it's hazy. Maybe a line in your ht or on your stat sheet. I also think you should be able to easily tell if you're drunk. I can't think of any reason why that would be obscured from the player - I can tell how drunk or high I am in real life, or at least get some idea.
People who get toxin binders are essentially giving up a cyberware "slot" for a benefit that is currently not all that worthwhile, and drugs are expensive, time consuming, and stealable on top of that! Binders should give healthy people a -lot- more leeway.
Picking binders instead of, say, synaptic stimulus should probably give someone the ability to temporarily boost their speed (or whatever stat) up a bit higher than the stimulus would have if they're coming with a comparable PDS load.
4. Creation time
This also seems fine. A lot can happen in the amount of time it takes to produce most drugs. I think if it was any longer it'd make production a lot riskier financially and if it was shorter there would be way too much product.
5. How long it takes to use (needs to be long enough for another player to attempt a disarm)
I think anything more than one turn total is not going to see any use inside of combat. SD already disproportionately advantages the attacking party. Remember also that someone shooting drugs might not have their weapon out and will have some inventory juggling to do that might take up more time/typing/turns/etc.
6. Availability
Players and factions do a good job with production and distribution, and anywhere they fall short, staff could opt to have like ViriiSoma or NPCs from some faction or another start pushing.
It might be interesting to take v-202 and ex-d7 out of the machines and limit them to corporate requisitions, factions, and PC manufacturers.
7. Strength of effects
The recreational drugs are too weak. Yes I know cocaine doesn't actually make you into A-Train IRL, but this is a video game, and mRc isn't cocaine. The downsides are many (and drugs aren't free), so taking a hit or two should feel like a pretty significant boost.
I think nanos work as a good gamefeel benchmark. Drugs probably shouldn't be better than that, but maybe the really good stuff could get close.
8. Strength of after effects
I absolutely think you should get ridiculous hangovers if you took a lot of cyber drugs. Also I think Endoprine shouldn't ding endurance when it fades because that interferes with its whole anti-PDS schtick pretty badly.
9. Duration of after effects
These should never last longer than the high did, and in the case of drugs that have a lot of negative side effects while you're high, they maybe shouldn't last long at all.
10. Withdrawal scripts & effects
These should be quiet and internal but convey a sense of urgency. The recent Nevadone one by Ephemeralis is fantastic stuff. However I do not think you should get withdrawals at all unless you are addicted.
11. Addiction
Currently you get addicted 100% of the time if you use drugs a certain way. I have lived an extremely colorful life and that's not really how it works. I know these are cyberdrugs and ViriiSoma wants people strung out on them, but I do think there should be checks against the user's endurance and/or intelligence to simulate drugs with tendencies for physical or psychological dependence.
No that doesn't mean addicts are dumb IRL, we just don't have a stat to represent someone realizing that maybe they shouldn't smoke weed before they go into work even though they really want to.
I have also argued for more granular progression into addiction in the past. I still think that's a good idea. Also the Velosan/Hemostax/Vitality patches probably shouldn't be addictive.
12. Interactions with other drugs
Mixing and matching drugs to mitigate the downsides or maximize the benefits feels pretty CP to me.
RPwise I think drugs are working pretty great. I also think that with some gameplay tweaks the game feel would help make that feel a lot more immersive. Drugs should seem like a good financial investment for a character who wants to get mechanical benefits from them. Sorry for hugeposting.