This is a very short demo, but even at the brief amount developed, it shows great potential.

Mapping/Graphics
As far as the graphics go, they are really beautiful and appealing. To me, it looks like there was a fair bit of custom work involved in the detailed graphics, something it would be wonderful to see carried over to the sprites and monsters as well. At this point, I think this is the area where the game really shines.

One aspect that's a little odd are the number of NPC characters who are inaccessible/out of reach.

Battles & Grinding
Right now, there is a fair amount of grinding in the game. The first reason was due to the cost of items in the town, and the second because I kept hoping to level enough to make things a smidge easier in the boss fight at the end of the demo (more on that in a bit). Right now, each of the three main characters has one, primary spell. That spell does a great deal of damage, but it's also pricey considering the amount of magic each has. This also means you're largely mashing space to get through the battles.

There is, however, an interesting system in place where enemies will drop and you can find treasure chests with battle cards. These cards are a variety of different magic types. I might have found this more useful if I were willing to use them, but since they were a bit sparser, I hoarded.

Town
I felt like the town could have been developed a bit more. While it was graphically beautiful, nothing in the town served a whole lot of purpose other than the stories and inn. Furthermore, there was only one piece of new gear that everyone could equip and only one character specific piece of gear. No new weapons or new armor at all.

Story & Dialogue
Right now, I think this is the weakest area of the game. You're launched into the game with no info about who any of these characters are, what there motivation is, how they are connected to each other, or even what they are doing. You really don't get any info about the characters until the end of the demo. What you do learn is intriguing--enough so that I wanted to delve into the story more--but also confusing, since you don't know what the heck is going on.

This dialogue/story weakness also shows up with the NPCs in town. None of them have anything interesting to say, which sort of sucks a little bit of the fun out. There aren't any sidequests (at least not at this point) and there is no reason to really explore because I don't think there is anything hidden either.

Minor Errors
I only noticed a few things. One was in the end demo (I forget the name of the building) study--the room with two seals covering the doorway. Even after you deactivate those, you still get the "seal removed" message when walking through the doorway.

The second thing was just a tiny typo where dialogue uses your instead of you're (the conjunction for you are).

Final Boss
Way too powerful. I admit, I had to cheat to defeat him. Even grinding up levels (I reached 18), he was still too powerful, and I didn't have near the supplies or the right type of battle cards to defeat him.

Overall. . .
I think this game is in its early stages, so while I list a great number of things that could use improvement, I do believe that, with a little work, most of these things could be smoothed over. In particular, much of it probably has to do with developing the story and interactions--both among the characters and between the characters and NPCs. Maybe throw in a few sidequests, even if it's something minimal like finding X number of plants--to add a little variety and help characters score some item/equipment/reward that they can't buy. I definitely do look forward, though, to seeing how this game develops.