[Lunaryon]

Have the Squib Parent having a love for Potions, given that it's one of the few magics that s/he can use, which also gives your character a little bit of background knowledge into the subject.

I'm a little confused about what you mean as a Wand Obsession... Can you explain a little more?

Next handful of things are a little easier, because personality doesn't really tie in:
Gender
Hair length/color
ethnicity
eye color