This does sound like a pain in the ass. Can I buy just tablets from a NPC and be sure I'm not going to get killed by a lucky snake?
There was a post above mine that went missing but expressed concerns I agree with. I can't help but feel that this should have been a "Not broken don't fix" situation.
This is actually a case of quite broken - trying to fix.
The old system was almost entirely a matter of ooc knowledge from one character to the next in the making and use of cures. The intended manner of experimentation and learning through tastes and colors wasn't working due to some building errors. The old system only 'made sense' largely through repeated exposure.
The new system is still being discussed, and updated, daily. Giving up on it at such an early stage because it isn't an extension of the previous, ooc-knowledge-required, system seems...well, what kind of progress would the game ever make if that was the measurement for accepting changes?
With regards to NPC tablet vendors, this is a good example of "just" being a four-lettered word. The outdoors is a dangerous place - filled with...danger. While a predictable system is to be striven towards, as is happening with these posts, as part of making it a manageable danger, there's little point in introducing one that makes it a negated danger.
We could "just" as easily give players a command that removes all poisonsto save players the trouble of going to the NPCs in the first place.
Ideally, once we move off of the old brew system, the cure crafting system will produce items intended by the crafter in terms of cure, poison, and within some ranges color. How these cures are distributed (clan save rooms, pc-to-pc sales, clan vendors, mini-quests like the cleaning solution) and how they are verified is still in progress.
Straight up NPC sales seems to cut a lot of PC involvement out of the loop and shift the game more towards single-player in a multi-player environment.