I don't think the moveset is TOO difficult (except maybe when it's charging at you, which is pretty hard to avoid).
I found it hard to beat at first, because to charge your attack, you have to spin through it, so you're necessarily putting yourself in danger. But after a while, once you've got the hang of this game mechanic, the hardest thing is to endure the fight, I think. Also, the dragon does a lot of damage to you, so it takes a while to get up, and sometimes no sooner do you get up than you take damage again.
But honestly, I don't think the game is unplayable. I've just replayed a game and I'm more than three-quarters of the way through its life gauge (unless there's a second phase where you don't get your life back, in which case I'll be screwed xD).