Took me a while to get the ebony blade upgraded. Looked at the wiki for a list of characters I could use to upgrade it and noticed most beggars worked. So I went around Skyrim finding beggars, giving them gold, and then killing them.
Unfortunately 1 I couldn't find, 1 was a kid and I don't have the killable kids mod, and several of them were marked as essential. Thanks bethesda. Anyway, to round out the rest I needed looked around and hired mercenaries since the wiki said they counted (as well as fendaal), brought them to Helgen, and killed them. So there's currently a large pile of bodies outside Helgen