Hey, just finished. The "Hero's Realm, but with story" approach is pretty interesting, as were the battles. Allow me to unleash some bullet points.

-Probably my biggest problem was the lack of easy access to items in Wachenta. I ran out once about halfway through and had to walk all the way back to the city, and just barely had enough to scrape through the boss fight. An in-dungeon shop or Phylomortis-esque "commerce sphere" item that gave one-time access to a shop would've been nice, especially since you don't have enough money to get all the items you need until you're actually fairly deep in the dungeon.
-What happened to Deckiller's rope from the castle to make you have to pick up a new one in the dungeon? Especially peculiar because it's not removed from your inventory when you use it in the dungeon.
-It looks like it's possible to permanently lock yourself out of one of the rooms in Wachenta.
-Having transparent tiles in a boulder-pushin' maze isn't a good idea. I recommend you remove the ceiling tiles that rocks can (and must) be pushed under. Also, there should be a way to escape if you accidentally block yourself in.
-The big boss was a good challenge, but I wouldn't have minded him being a little slower. Also, you might like to consider having someone point out that it's best to go all out once the boss breaks out the Ruin spell.
-I would have liked to be able to go over secondary skill descriptions again after the time they pop up when a character joins.
-How often are you going to be busting out the FFXIII music? I can see it getting old real quick, like what happened in Legion Saga III.

That's all from me. Eager to see more!