[url=https://static.wikia.nocookie.net/finalfantasy/images/c/c7/FFXIV_Eden%27s_Verse_Ramuh.jpg/revision/latest?cb=20200305094355]Aaron's Final Form[/url]

So I think I've found his "Final Form" as it were. I can't remember what the next step for us Aeons but this is what I think that Aaron will look like.