You know what I think could be a really interesting idea, is if romances are included you could have some kind of influence over them.
For example, you could be prompted at the begining of the game to choice a few different 'styles' of romance. Maybe you could decide that a random companion you meet will start to have feelings for the main character and persue you not the other way around. Perhaps you could choose that there would be un returned love between you an a character, or you could even pick that perhaps your character has an arranged marriage or something like that.
It could be a different way to handle romances instead of the normal trying to "woo" a companion. On the same note I would love to see companions beyond the main character start to gain feelings for each other, and perhaps you could either encourage or discourage that.