I just look at CV Judgment in the same way I look at FF Dissidia. I don't take the story too seriously, and otherwise, it's cool to fight it out between some of the series' best characters. As for the designs, well, I'm an Obata fan from Death Note and don't mind the different appearances for a one-off title like this.
Frankly, I'm glad Judgment didn't go the route of a conventional fighter. Castlevania is often at its best when it feels like an "A-list classic gone B-list next-gen series", if you know what I mean. I think that's part of what I dislike about LoS. It tries too hard to appeal to mainstream action gamers, but since it's not as good as Bayonetta and doesn't fit into classic CV lore, it resides in some uncomfortable limbo that makes me unhappy as a long-time CV fan.
Ultimately, I like CV Judgment for what it is, but I don't think we need to see any more entries like it for quite some time.