Her favorite food should be something common and easily obtainable so she will be able to be happy most of the time. I'm thinking potatoes, that way if one of the team members accidently upset her, they can offer her a 20lb. bag of potatoes and she will forgive them for thier transgressions. Also, potatoes are ever so tasty with a little bit of butter and bacon.
Favorite color, I'm thinking green would be a nice favorite color. I really have no reason for this so here is a picture of a
dog in a hat instead. Now you must agree because the cuteness of the dog in that
green hat will overwhelm all reasoning.
I think a good favorite weapon would be grenades personally, more explosion-y that radiation arm cannon. Maybe turn that arm-cannon into a arm-grenade launcher. But yeah, also Grenades come in different flavors such as frag, ion, plasma, gas, flashbang, etc. so they are versatile enough that it wouldn't unduly hinder her to have a lot of grenades on her person at all times.
I would like to see her favorite armor be... NONE, just kidding. Her favorite armor is obviously clothing made by herself from the leather of her radiation victims. Bonus points if the leather still has metal shards in it from the grenades she tossed at them. Plus those metal shards should be able to help protect her somewhat.
Her favorite treasure should be. . . a golden potato. Extra points if she starts beating up anybody who accidently calls it a golden egg. Also, the golden potato can be used to buy things with, in times of desperate need. Then she could just radiation the merchant to kill him and get her potato back