You should re-read your Dante
On the whole, I like this series. However, I can never get past how much you changed the geography of Dante's Inferno. While I can understand you skipping over Limbo, and changing a few things around for the purpose of moviing the story, there are several things that just BUG THE SHIT OUT OF ME:
1. Changing Virgil from a virtuous pagan(and therefroe a resident of Limbo) to an evil slave of Minos is just annoying.
2. The River Stix is located in the fifth layer of hell, where the wrathful and sullen are punished. You, however, have put it on the fourth layer, with the horders and wasters. If not this, then you've clearly had the circle of greed take up two layers.
3. The chaging of the punishments for the 4th layer. I understand what you did with the 2nd layer, and it worked. This, however, does not. It would've been much more interesting(and not to mention potentially more hilarious) if you had retained the bit from Dante's Inferno where the greedy are at war with each other. After seeing how well you pulled off the third circle, I know that you could easily do this.
Other than that, I like this series. It has good voice acting, fluid animation, and witty humor. You should just try to get the geography of Hell right.