if you want her to deal more with her autos you'll want either nashor's tooth or lich bane (or both). nashor tooth gives her more sustained damage with the attack speed which lets her proc her passive more often. lich bane gives her more burst since it adds good damage to her combos (but she has no many reliable ways of constantly be proccing its passive).
i think that with the passive buff jungle diana might be pretty decent.
Just fooling around in a custom game the passive is pretty damn big. Once I picked even an amp tome clearing times and sustain (w/ spirit stone) were excellent.