Perhaps something like this:
If romanced an occasional (or related to more gifts/affection gained even beyond max) .1) some flirt scenes/options. 2) random poking fun of other companions/options 3) of course, what everyone wants; but too chick**** to say... more sex scene options.
I'd really like the DA:O option you had of just a random 3 second cut scene of "hug him/her" or "kiss him/her".
I used to love hitting the end of a really grueling battle in DA:O and then running up to snog my character's LI. Ditto if I happened to let them fall in combat. Kinda like 'honey you're alive!! *smooch*' lol.
It just adds a little more depth to the relationship between the characters. And it would be funny as hell if you are in a group lol. I could just imagine my partners characters LI (Yes he caved in to bioware's evil ways and romanced his sith warrior lol) pulling a face when I run up to Andronikos covered in blood and gore and snog him senseless in front of everyone! I hear Malavai is a little straight laced *snerk* rofl.