If I say what I like, I might actually spoil my own novel. XD
Kidding. I actually go for the nerd girl since when I progress the game, I always go for rolling fast in dough with INT. If not, I prefer either go for the energetic girl or the onee-san. If she's both, thats even better.
To be honest, while I am dumb when it comes to relationship, I always seem to be quite excellent when it comes to galge. Not as comparable as Katsuragi(God only knows, also known as god of romance). Its kinda scary for me since even though I mostly rely on instinct in my everyday life, when it comes to galge, I would always pick the correct route for romance options like my brain is hotwired to perfect a route.