I think MercurySteam doing a 3DS game may not result the same qualities Lords has achieved, if only because they're working on two DLC episodes for Lords AND a sequel to that already, which I assume will be for consoles.
I'd rather have IGA do a game, if only because he's proven to make quality, albeit somewhat derivative, games. His main team hasn't made a game since Ecclesia. Adventure Rebirth was made by M2, Judgment was made by Eighting, and Harmony of Despair was largely developed by Westgate, and IGA only had producing roles in those titles.