Giving Sarah the ability to draw exhibit items instead of unique items is problematic to say the least; what if she's shopping at the curioustie shoppe? how could she buy exhibit items when they have no list price? because her ability is so minded is the reason I have her a free +1 bonus to her focus.
Now, regarding edmumd, he's not as broken as you make him sound. Even with a Speed of 5 he can't gather clue tokens from more than two locations in one turn. Aut-evade on all monsters in the street is much more broken if you ask me.