Boiled Water / Tannin Tea is worth too much.
All the places where you can sell sterilized (boiled) water are perfectly capable of boiling water themselves; it doesn't make any sense that they would be willing to pay such a premium to have their water pre-boiled. For that matter, they would probably re-boil it themselves anyway, because why should they trust this random dude who just sold them water and tells them it is sterilized? Similar reasoning applies to tannin tea; though it should be more expensive than water, it shouldn't be so much more so.
From a balance perspective, selling boiled water (or tannin tea, if a Botanist) makes it far too easy to make money; it's not like you're the only one that knows how to make a fire. Boiled water should be only marginally more expensive than regular water (twice as much, on the outside, in my opinion).
If you want to be fancy, it would be potentially interesting to have "factory sealed" water, or something of the sort, which would be the water you find in sealed plastic bottles when scavenging. It would make sense for *that* water to be relatively valuable.
Another related improvement, I think, would be to separate "bark" from "twigs". Bark should not be easily obtainable in infinite supply as twigs and branches are; it should take time to gather. This could either be done with making a crafting recipe which combines a sharp object with the forest object to get bark, or simply by making bark only obtainable through scavenging forest tiles, rather than just "use"ing forest objects.
Just my two cents, and suggestions. Thanks for the great game.