After looking into it, it does change the formula up enough that I'd be interested in it.
That said, I probably won't get this. I don't have the huge familiarity with Dragon Quest that I do with Legend of Zelda, so there isn't quite the same draw. I'm not sure if these characters are drawn from previous Dragon Quest games, but I actually get the feeling that their an all-new cast (as most DQ cast members don't go past a single game). This means that there isn't a huge draw of familiar characters I know and love to pull me in, which really helped Hyrule Warriors.
Finally, while the party mechanics specifically do look interesting... I've still got a ton of stuff left to do in Hyrule Warriors. Maybe once I'm done...