The game is still too hard
It is good when things are hard, but it is not when things are unfair. So I made sure the game is more hard than it is unfair. It will take many tuning passes to achieve perfection, but I want the game to feel fair and fun while being hard as nails.
A few bugs were preventing some mechanics to trigger, rendering the resulting experience less rewarding and less fair. I do not want any bugs in my game, so I got rid of them and now it feels better.
Content will not stop coming 
The game is far from being complete. It is far from being ready even for the early access. So I will be adding a lot of content and other features to it. And some of it will be available in the demo.
I do not like when a developer drops a demo and then never ever updates it, focusing only on the commercial release, while the demo is being outdated and obsolete. So I won't do it like that, I will be updating the demo for as long as I can, adding some new content to it once in a while.
There's more things than you can see initially
Like any self-respecting dungeon crawler, Legion does have a lot of things locked behind progression and achievements. Easy mode is one of them, but you can also unlock new rooms, items, spells and features as you explore the dungeon.
P.S.: if you unlock something in the demo, you can have it for the full version too.