I just finished this game and imo, a 6-7. I reasonably liked it and don't regret the purchase, but I definitely felt like this was made by a B or C team. Maybe it was the juniors Kondo mentioned... The shaders are trash, textures are bad, story is mid, character shading is pretty bad too. There is also some weird surround lighting on the characters (not rim lighting, which is just awful as well). The boat sections suck terribly until you get mana sails and some upgrades. Oh yeah, no weapon models outside the first and last, which with only two toons seems lazy.
FYI, I just replayed Ys VIII last year, and I prefer it easily despite its Vita roots. I am not sure where I would put this one, but below 8-9, Celceta and Origin...probably 6 too. Hmm, now that I think about it, I don't recall 3 and 7.. (or 5 for other reasons).