Good level design, but stiff controls
First things first, let me just say that I enjoyed this game a great deal, and have played it through to one hundred percent completion. This is a fundamentally good game that just has a few key issues; the game's world (from the overworld to the levels themselves) is rich and rewards exploration. The author did a good job managing the difficulty of hidden secrets, and I felt like I was actually exploring and making discoveries. Kudos to you on the world design, author, because it did its job well.
I feel that the primary weakness of this game is controls. Control of the wolf character is a little stiff - particularly in midair, though the wolf seems to have some hesitation changing direction on the ground as well. Interacting with enemies was awkward, primarily because of the stiff jumping controls making it hard to land on enemies, and sometimes it feels like normal running speed (excluding exiting a slope) should be just a hair faster.
Speaking of play control, there were a few things that were not particularly intuitive, and not explicitly stated (to the extent of my memory) in the game - in particular, midair rolling, which turns out to be quite important. I discovered the ability to break cracked surfaces completely by accident about halfway through the game, and it took me forever to figure out how the black wolf's wall-jumping works - I didn't expect to have to keep holding up while going back and forth. Speaking of which, I only discovered the black wolf training area long after I had earned the black wolf. If a similar area exists in the next game, I'd recommend making it easier to find. :)
Other reviewers have mentioned the character's animations looking a bit off, and I suppose I'd agree. It's not a breaking point for me, but it is a bit obvious that the wolf's legs are tweened in the run animation. Something like this will obviously be dependent on your animation experience, so I'm not gonna be too hard there.
Honestly, I enjoyed the game quite a bit. This is a game, I feel, whose strengths aren't as apparent as its weaknesses at first glance. I'd recommend any prospective players give it a little longer than the play controls might suggest - once you've figured out how to handle jumping and rolling, the game's levels offer a pretty decent game experience.
I'm looking forward to the next Jade Wolf. Keep up the good work. :)