I think its just a balance of a lot of factors. For instance I am loving DQX1. Yes it is a bit simple but its keeping me engaged. I've never played DQ and I did pick the one option where weak enemies don't give XP.
I think the ways a game hooks individuals is interesting. Honestly with DQX1 I'm more disappointed in not having all the equipment be modeled. To me it is a lot to do with new mechanics throughout the game being fed to the player. Things like collectables and upgrading really matter. That along with some customization for characters. But none of this matters if nothing is balanced and there is no real strategy,.
I'm looking for a game that melds character building, visuals, active or turn based combat and a decent story. Its something that doesn't really exist.