The smoothness of the 3D here really can't be understated, it really is completely seamless. While normally a pretty simple thing, the diagonal running animations also are a really important touch that contributes to the fully 3D feel of the game. This seriously looks awesome. If your engine can handle it, I would like to see some kind of platforming or verticality so that the third dimension can actually do something other than be a cool graphical illusion.
Gameplay-wise, there's a lot missing. As others have said, the camera is too zoomed in to have much spatial awareness, and it's also really hard to make out if you can hit an enemy from front or behind (it just makes more sense to run around and attack from the side.) The single attack, lack of dodging, blocking, combos, etc. make this feel almost like Sword of Vermilion in terms of blandness, and as an unfinished game there's obviously nothing in the way of upgrades or progression yet.
Honestly the only thing this game needed in order to succeed was a teammate to take care of some of the boilerplate code needed for a combat and inventory system.