"As for role playing, the game will incorporate relationships that other Obsidian RPGs have used, but there won't be any romantic options."
http://www.polygon.com/2014/6/19/5823118/pillars-of-eternity-preview-e3-2014
Full featured role playing games often use romance or marriage systems. Amazing games such as Baldur's Gate II, Neverwinter Nights, Skyrim, Knights of the Old Republic etc. As a backer, personally I'm disappointed in the lack of romances in Pillars of Eternity.
For fans of this style of optional content, there's no upside to their absence.