I would rather play an HTML that's just text than one with real pictures. The pictures and poses never seem to fit well with the story and most times the developer relies on the picture to carry the ero and that leaves the writing with much to be desired.
Don't know if it's considered a mini-game but in games where you have to progress or get affection points, you have to go to a specfic place and time just to get one point and it advances the time so you have to so the same thing daily to get enough points for the next scene. At least put some...
Any type of relationship as long as it's either younger male/older female or smaller male/larger female. It could be a 40yr old brother and a 45 yr old sister, and it still hits the spot.