Outlines definitely are useful, I've been trying to make them more. Actually, in a round about way, my second draft (which is in synopsis form and drawing from multiple planning documents) is my attempt at outlining/structuring my new revised plot, but my focus is poor and never actually wants to outline even though it makes writing so much easier. xD I've never tried researching historical characters though, that sounds interesting, I'll have to try it some time!