My God-Emperor of Mankind conversion has had a bit more work done to him - he's now got a head, a combi-bolter, and a great big flaming sword. I've got a couple of wreaths on order to add to the heads on his knee and shoulder, and obviously he needs the big greenstuff cloak and mantle. But he's getting there!
Originally I was sure I had a Grey Knights Dreadknight sword lying around, which I was going to equip him with. But I couldn't find it, and then whilst searching my bits box I found the Balrog's flaming sword. I instantly knew that that was what was needed! It's sadly only single-bladed, but a flaming sword is an iconic part of the Emperor's armament, so it feels right to me.