hearing other npc's around the town you live in saying congrats and talking how beutifull your wife is?
or hearing them talk to your wife how lucky she is?
and she gets killed? it revenge time! looking for glues etc,
allso your wife would be at the home of "champion" ppl coming pleaing for help for you to hear (if she remembers) when you come home
no child making etc like in fable games, but great dose of immersion, all about belonging to that world (if you so wish you can imagine you do it when you go to sleep at bed)
allso lot of other quests could be centered around married life
is her father wealthy? he wont give her daughters hand for any riff raff from the street's!
who would like to kill her? well dragon could attack town ofc, there will be many maidens who are jealous about her? and no matter what you do you allways make enemies who are willing to kick you where it hurts.
just my idea of good immersion? would give addional need to go hunt those pesky dragons, slavers, monsters that would attack your home town!
well this kinda thing could be hard to create but still... just a small thought