Coming from DND 5E, this game was very, very easy to understand the mechanics of, and it kept things pretty easy for newer players to understand. Below I'll note some feedback. With the full knowledge of the demo is super early alpha, and many things are likely going to change, and the DEV team is most likely already very much aware of.
The only major bug I encountered was in the last area with the deep spiders, as I rotated the camera, very, very bright lights started flashing on the screen, Different streams of different colored lights. Until it's fixed you may want to add a seizure warning to your demos to avoid any liability. If I had been epileptic, this definitely would have caused an event (i.e. Think the banned Porygon Episode of Pokemon, it was that bad) Once the lighting started freaking out, it didn't stop until I left the area. Thankfully by turning my camera into the pitch black while not my turn, I ended up avoiding the majority of it, but I'm still seeing spots at the moment.
Going forward, I do hope the additional classes are added to the game, as not having even the standard set would be a pretty big disappointment. Maybe 2-3 more races at most by launch would be nice. I found the backgrounds and alignment tags to be sufficient, adding any more of those doesn't really feel as important to me as gameplay and classes, and would take away budgeting for voice acting and dev time in general.
Movement and running animations, this is the first thing I noticed, and I'm sure it'll be changed, but it's worth pointing out. All toons move in concert with each other, which logically wouldn't make sense that their right arms all go up at the same time and speed while walk/running(i.e. plate mail & Cloth are different weights, as are the races) It honestly threw me off and broke the immersion within seconds of starting.
Verticality & environments. I get what ya'll are trying to do in making areas more interesting, challenging, and realistic, but I found it to be a real hassle. Both navigating the different vertical levels, and camera control around it. Bridges would disappear, enemies would clip through stuff, and trying to move toons was a pain in the butt. With that being said, I'm not saying "Don't do this", but rather, maybe limit the amount in each area so our senses aren't overwhelmed. It was nice to feel like I had several options of movement with characters, but it was also frustrating at the same time.
Crafting. Obviously very limited time using it, but the things I'd be interested in crafting weren't available in the demo (Armor/Weapons/Poisons)
Anyways, all these are nitpicking, and I really did have a fantastic time playing the game, minus the spots, and I look forward to furthering the development of the game. Thank you for letting us get our hands on the Demo, it was great!