Here's my feedback after 4 hours of play time.
For of all - CONGRATULATIONS ! Your game is already better and far more interesting than a $5M funded game ( Ultima Ascendant, what a trainwreck ), so that's already an accomplishment. It looks, feels and plays better too.
I'll start with global feedback first. It looks pretty good ( in fact, better than most indy games ) and even if some assets are stock/generic, the art style is coherent and fits together. It's easier said than done. It runs extremely well too on my 6700k + gtx 1070. No slowdown or major technical issue to report, installation was fast, and stability was perfect ( no crash so far ). The screen resolution seems to be fixed to 1080p despite me playing on a 1440p monitor ( I'm unable to cycle through resolutions in the options menu ? ) so I'm getting a bit of aliasing / blurriness due to the upscaling. I'm also forced to switch my locale in english ( I'm french ) as there are currently no ways to rebind keys. The game seems to intercept the mouse focus, even when you alt-tab, therefore I'm unable to switch my locale after the game has been launched. No problem for now as it's an alpha, but for your first public builds this should probably be a priority.
My initial impressions were positive, especially in terms of visuals and ambiance. Controls were straightfoward but I instantly thought that the automatic leaning ( camera roll ) when you strafe left/right was overdone ( + reset too slow ) and might induct motion sickness on a lot of casual players. I'd recommend tuning it down or at least providing an option to disable it. Some negative points related to the coherency of the UI too: escape does not quit the menus / inventory, and when I first read the letter in my inventory, the mouse had disappeared ( until you left-click and it re-appears ) with no easy way to close the UI. I also dislike the context menu that opens up when you click on an inventory item, it's going to get frustrating when you need to do that for many items and requires extra clicks that aren't needed; my suggestion here is to stick to drag & drop on LMB and "use" ( or that contextual menu ) on RMB.
I noticed from the feedback already posted that darkness is going to be controversial. You'll probably want to at least add a gamma slider. On my monitor, it wasn't too bad and I kindda like the "oppression feeling" this puts on the player. There's a minimum natural glow around your character, torches and a lighting spell, so I don't think you need to change all that much. I found myself using the lighting spell frequently, and it does look nice; however it comes a bit later into the game, and the first torch you find seems to run out very quickly ( after 2 or 3 minutes it felt ? ), and I haven't found any torches in the first hour, so my advice here is to add more torches until you get the lighting spell. I found a stack of torches later in a room, but by that time you've already gained the lighting spell so it isn't as critical.
I think the game as it currently stands has a major flaw in terms of difficulty. In fact, I'm a bit confused as to what your goal with this first level is. Is it really supposed to be the introductory level ? Because the difficulity is high enough that it should be a mid or even end-game level, IMO. I'm not just talking about combat ( more on that in a minute ), but the overall experience. The caverns are fine as a tutorial with their tooltips; they slightly overstay their welcome and are a bit on the boring side, which is partially due to the low movement speed. The main issue is that once you start to open-up areas of the level, you get lost and you easily miss out important quest items or keys. The amount of back-tracking is already frustrating me and it's only the first level. Now, if this level was specially made as a vertical slice, and will later be moved to the mid game, it's fine. But if it's representative of what you want as your "real" introductory level for new players, I think you'll have to do many adjustments.
The first major issue is with keys. Keys allow you to open up various areas of the level, but there is currently no way to figure out if you've opened everything or if you've missed something. The lysdandria key is a good example. Without spoiling too much, it's standing on a small bench with candles in an alcove on a wall, and I literrally ran past this area a dozen times without seeing that there was a key here. Keys, in general, are absolutely critical to your progression, but they're small, without a visual indicator / glow, and easily overlooked. That, again, would be fine in itself if this was a level later into the game, but as the first level, I suspect a lot of players are going to miss out on keys just like I did, which will force them to run around corridors for more time than needed, leading to early frustration. IMO, every item that is either a quest item, either an item mandatory for progression, should have some sort of small glow / hint ( it doesn't have to be "in your face", but at least a little something ).
The second major issue is combat and the stamina meter. So far, combat seems to be the most buggy part of the game. Some undeads seem to get stuck, stop reacting / attacking and it even happened to myself a couple times too. In one occasion I was unable to attack, defend or move at all and had to stand here in front of a frozen undead. I forgot how I unstuck myself, but something was definitely bugged. In general, stamina usage seems to cause a lot of strange behaviors. It seems to me it can go negative if you keep attacking for example, so if you do not pay attention, it can take a while before it starts to replenish. In another occasion, after a serie of attacks, and despite standing still and doing nothing, my stamina meter stood at zero for a good minute until it started to replenish again. But those are technical issues; In terms of design, I'm not convinced by that stamina system. I do like that you need to time your attacks / defense carefully, to not exhaust your stamina, but there has been plenty of cases where my stamina was at zero, and I was getting stomped by an undead, so I basically could neither run away nor attack. It was checkmate, but I was still alive, while the undead kept attacking repeatedly without pause; so I could stay alive forever, but unable to run away or to attack back either. Frustrating, and it happened frequently. It felt like a black hole: once you get there, you cannot escape your fate.
Another issue with the combat system is that it seems to me that attacks are modulated by the stamina level. In other words, you do no damage on attacks when your stamina is at zero. My first experiences with combat were very frsutrating as a new player; as I didn't realize that my attacks dealt no damage, I kept attacking and defending myself, but my undead opponent took no damage ( despite the visual feedback ). After 10 minutes, it felt something was off and I wondered if I had missed a more powerful weapon, or if my opponent was really invincible. So at the very least, you need to teach the player how the stamina system works, and I would also recommand increasing the minimum damage you are doing when on low stamina.
The stamina system also ensures that 2-vs-1 is extremely hard, next to impossible; I've died dozens of times so far, and that was often caused by a second enemy joining his mate I was battling. On 2-vs-1, there isn't much you can do, as you can't parry all the time, and there are no openings to attack any of your opponents either. That makes the current demo thrilling (in a good way) as you have to be extremely careful, but emphasizes the issue that it's really bad as the first player experience / introduction to the game.
The third major issue is the save system. I had to double check to be sure I didn't dream it, but no: the enemies reset on saving at altars. This is not cool, at all. I could somehow understand resetting enemies when dying, but that's not even what I'm talking about here: I kill an enemy, go back to an altar to save, and when I come back, that same enemy is back. I'm also losing experience points, and when respawning, it's not a real "reload", so the consumable items I had in my inventory ( and used previously ) remain lost. The consequence of all of this is that you cannot really game the system ( for example by killing enemies one at a time, saving, so that you can ensure minimum progression even if it's too difficult for you ), but in fact that as you keep saving / dying and losing consumables, your chances lower and the difficulty keeps increasing. I'm hoping that in the future you'll implement a true quick save / reload system instead of the current one, which reminds me of Ultima Ascendant ( and which was despised and criticized by almost everybody, if you recall.. ).
Finally, if we except combat, in terms of quests / progression, I also think this level is a bit too frustrating as the intro level for new players. I'm particularly thinking of the gemestone "treasure hunt" which asks you to backtrack to the beginning of the game, and makes you doubt if you have found the right location. It'd be fine in a mid-game level, but in the first level I can imagine that a lot of new players would ge frustrated.
Verdict: a solid alpha with a lot of potential, but I have my doubts about the saving system, the stamina/combat system and overall believe this level isn't a good fit as the introductory level for a casual RPG player.