Thanks for trying out and for your feedback.
Few things:
1. Skills reset mechanics, of course, will be available in full version. It supposed to be unlocked later on (it simply is not needed in such short demo)
2. Specialization is quite difficult to combine with no-prestiges concept, cause it will hard lock people from trying all content. That's why I decided to make it like: "improve everything you can, but in order and pacing that you feel comfortable for you"
3. Yeah, skill tree is something that I still have to balance properly.
Thank you again for trying the demo and posting feedback here.