I'd like to choose Yui Horie as Tsukimiya Ayu (Kanon), Youko (Inukami), Sasakie Makie (Negima), Sawachika Eri (School Rumble) etc.. etc.. (just too much
http://en.wikipedia.org/wiki/yui_horie for full list...). She can change her voice into several different types (for my ear). You should notice the different beetwen those role i mentioned above...