Looks come in somewhere, and my very first impression is generally based on looks (because I know nothing else about him at the time). But as time goes on, my opinion of him may shift due to getting to know him. If he doesn't have a good personality (is rude, judgmental, etc.) I will not want to be around him. However, if he is "unattractive" but still has a good personality, I'll likely want to be with him (friendship, maybe a relationship depending on the situation). Personality really does matter most for me. I also think that a lot of times, someone's "unattractive" features can become extra things you love about them (their ears that stick out, facial scar, crooked nose, etc.). Hope that helped. Lots of luck :)
My first reaction to any guy is their appearance. But once I strike up a conversation and they are intelligent and I have chemistry, (and they are not that attractive), they BECOME more attractive. It's weird because I don't have a type of guy that I go for. I've dated all different kinds of guys.
Ex of guys I've dated:
Ex 1: majorly obese, but treated me like a princess and we had great chemistry.
Ex2: Irish, short and petite with red hair. Smart butt and completely crazy.
Ex3: A Cambodian with long dark hair to shoulders. Tall and a freaking jerk most of the time, but has sweet moments.
All three of these guys are different in every aspect possible. They are the guys I've dated in the last year and half. They all LOOK different and ACT different but I was attracted to their personality and how they treated me in the beckoning everything depends on personality for me. Not looks.