I agree with Macbeth and Ubereil. If I had 10 minutes for gaming I'd play solitaire or mahjong. If I wanted to raise a pet or micro-manage a building / region / economy, I'd buy an appropriate game of that genre.
That said, these elements can be added to an RPG in a beneficial way. A pet could allow you to customize your party and character, as long as it provided some use (preferably something unique to the type of pet) and didn't require a lot of babysitting. If you can build and manage a castle by actually interacting with characters and have the result be determined by your choices and previous quests, that could be good. If you have to tell peasants to go gather resources and bring them to the appropriate building, etc, you'd end up with a genre mix that probably wouldn't work (it wouldn't for me, anyway).
DD had a good mix of combat and quests, and was fairly open, so there were few places in the game where I couldn't do whichever I was in the mood for. If DD2 incorporates some shorter (non-Fedex) quests, mini-games or other diversions, that's fine, but my main interest would be with the core RPG.
