To me good personality traits are kindness, humour, fun-loving, quirky, geeky, ad ambitious but different personality traits are attractive to different people.
If you look for the bad things you will always find something you dont like because there is no such thing as a perfect person. Ask any couple and they can tell you something about their partner that annoys them. It is however good to know what big factors would not work for you (such as the clingyness of your first gf)
Also if you only like someones body that's called lust