Regarding alchemy, when you select a location on the side of the map, its name, enemies, and ingredients that you can find appear, remember many of the stories are made by guest writers, if they do not consider it, hyao will not be able to add anything
IIRC plants and enemies only appear after you find them or fight them, respectively, for the first time, not before. Even then, one of the alchemical ingredients I needed was on the forest path, which only unlocks after defeating the bandits. I simply was not interested in doing their quest for a long while.
I started out with the Lizards, and after their main quest began to focus on the rat men and werewolves simultaneously. So I had a lot of areas unlocked and eventually as the quest piled up I got confused as to where to go next because they started demanding ingredients I didn't have access to yet with no real indication that I recall on where to find them.
A reference guide at the house left by your missing master that hints at or tells you where ingredients are even if you have yet to find them or unlock the area they are in would be a nice touch IMO. It makes sense in-game and avoids being too hand holdy at the same time.
Unexplored areas (some of them not the hidden stuff like the ruins) topside should be marked on the map but not accessible (Lore wise it'd make sense for an alchemical master who travels all over the place to leave behind a fuller map in his house of established regions and pathways). Practically, that'll give players some direction in the future to access the stuff they'd prefer to do first without needing to resort to online guides or quest grinding.
AKA I need X,Y,Z it can be found at B, which is behind the bandit camp. And there you go. You still need to navigate the quest on your own and figure out if B really is the reason you can't access the area.
Regarding the letter that the teacher must leave, he does it at the beginning and communicates with you later, many of the things are unknown when you progress slowly in the game. It is a game that has intersecting stories, that is why it is difficult for you to find certain things or objects. , but it is an extremely excellent game, look at many games, but currently it is the only one on Patreon since the others do not reach me the same as it is or their Patreons are paused, but hey, it is an excellent game, let the creator finish it
Of course it's a good game. That's why I made this account in the first place, specifically so I could come on here and leave feedback. I don't do that for many games, even official titles. This is the only itchio game I've commented on thus far. I also made it a point to say how fun the game was in my initial comment to avoid anyone thinking otherwise.
That said, if the creator is reading comments, which he should be, than feedback, especially useful feedback like my own (I'd like to think anyway), should be taken into account.
The letter of communication left by the teacher that you are referencing does not, as far as I remember, have anything to do with the mechanics I suggested and even if it did, it would come too late to matter.
It is difficult to find things in this game at a certain point because, I would argue, there is not enough direction provided to the player in the game itself. That's why he has a guide linked in the options menu and that's why there are plenty of comments even in here asking for help with certain quest. I'm not asking for quest markers mind you, but rather Morrowind style hints which are more than reasonable and currently do not exist.
None of this makes the game bad nor does it mean the creator isn't already aware of it. He must be if he has that guide to begin with. Yes, it might even be that my feedback is a couple months too late and he's already on it and if so that's fine. I'm just giving him possible ideas to address it in the future if he needs or wants them.
So unless you or someone else would like to talk about my suggestions in-depth, I don't feel it's necessary to elaborate further. I believe the game would wholly benefit from implementing some of the ideas I put forward here in the future, and I believe some of the stories could be greatly expanded if anyone who is responsible has a mind to do it and I see no harm whatsoever in letting that be known to the developers.
When, how or if those things get implemented are solely up to the people responsible for the game and everything I have said has been polite, fair and reasonable, and I'd like to continue providing feedback for this game for the very reason that I enjoyed and enjoy it as much as I do.
That's how you're supposed to contribute to things you love, try and help it grow into something even greater.