When you first walk near an interactable the tutorial system will popup saying "Space : Interact". This includes items as they're an interactable, but it only happens once and so I guess this isn't good enough. I can add another controls popup specifically for items saying "Space : Pickup item". That's very easy to do.
You mentioned the "trinkets" being unobvious, but it says "Equip artifact" when you hover over it in inventory, isn't that good enough?
I'm not sure what you mean by light being difficult to master, more light = more easy game, because you can see the enemy as opposed to not seeing the enemy. I guess the only thing I would be concerned about are players not utilizing their Seek Glowbug ability, which is there so that players don't feel completely crushed by being lost in the dark. (though Glowbugs are missing in the deepest areas)
"Regain stamina on kill" was one of the stat variables I didn't spend much time on, so I might implement that idea. There is a slight intention to make stamina start as "something you are required to manage" to then level up to "being virtually infinite". This isn't souls where stamina is always something you are required to manage no matter the level. The combat is faster with more opponents, no one's got time to stare at the bar in the top left.
I find it funny you like the spears, I don't like them at all. I actually thought they might've needed to be longer. The ancient TV which I use as a monitor has some input lag though so precision is a little harder.
If you have trouble with the Cactus monsters then I would chalk that up to your poise damage not being high enough in order to stunlock them. Cactus have the highest HP in the game apart from bosses, and the poise levels of monsters runs parallel with their HP.
Yes Bell power granted relates directly to the XP of every monster that is aggro'd by the bell at the time that you ring it. At the moment it's 40%, so ringing a bell then killing every aggro'd enemy will grant you a total of 140% power. It should be possible to find the Bell once in every area, if it's unfindable then enemies probably broke it. I've debated it with myself and I probably won't remove the bell from Central because I want to train the player to abuse the bell because some of the most fun I've had in this game is ringing a bell in a deeper area then running back to Central to level up while I'm being chased by 50 guys in a dark maze that has newly generated (since going back to previous dungeons alters them).
"However, you should really give some indication on this. Some players will probably think that there is no progression in the dungeon."
I'm not sure if that's necessary, because the player should recognize that they're discovering new enemy types by venturing deeper. So what happens if they keep going deeper? Discover new enemy types forever? No, you discover the boss. The music stops to indicate that something is up. Also there's 4 strange icons in the level up screen when you hover over "Continue", I'm not sure if I should have added accompanying text to them.
There is a potential problem where the player doesn't explore the deepest area properly and doesn't find the boss. Would this be considered a flaw? Surely players would properly explore the deepest area.
An issue with overhauling level progression is I'd have to playtest it and I'm sorry to say but at this point of development I'd rather accept flaws that are core to the experience than fix them. Because I want to move on. For example I don't like the terrain perspective (that zelda crap I went with) but there's no way in hell I can change it now.
Though I don't personally consider linear leveling progression a flaw. Maybe Dark Souls is the one who did it wrong, did you consider that, eh? I bet there's a lot of dark souls players who didn't know about the softcaps and ruined their builds!
Version 1.00 won't be changing anything major, just some bug fixes.
It's a free game, I won't be selling it, dev is a hobby. It's the greatest free game ever made! (well those are some big shoes to fill so maybe not)
Instead of buying, tell others about the game, I need more feedback before I'm done with it. Marketing is hard (is marketing the correct word to use for a free game?), consider me as someone who doesn't like talking to people despite these walls of text.
By the way, tell me if a lower Gamma value looks better. In ESC menu go to Graphics -> Colour Profile -> change Gamma to 80 or 90. You may be surprised to see Blue at 130, but you will be even more surprised to learn I designed all my art on a crappy low budget TV and had to create a colour correction shader to fix it. I think the gamma may have been incorrect too.