For my part, it's the Fallout series. I know it seems strange, but the same guys who worked on Fallout 1& 2 can't possibly produce a bad game On a more in genre style, that'd be NWN series.
I also think that sidequests related to the optional ownership of one or more store in one or more location would be a nice way to add to the game without a heavy emphasis on that aspect.
I do understand that it is a cRPG and not a trading game. But could it be possible to own stores and participate to their success in a limited capacity in order to have a steady source of income?
I've always liked to loose a few hours of gameplay on this kind of stuff. That or an elaborate crafting system.