[@Eevui] Hmmm... their heritage could work out in the roleplay as long as you have it make sense. As for their affinity for black/white/aether, I wouldn't mind as long as you don't make it overly powered. I was going to have it that characters had to have a "main" job that they're an expert at, and they're only mediocre at the other types of job. So yeah, your character can start as a conjurer OR thamaturge, but I would prefer if you choose one in the beginning. 

To make this more clear: your character starts off as an arc. Then, later down the line, they pick up conj or thm. You're gonna have to choose if he is better at being an arc or conj or thm. As for him being a hyur and (later) being a rdm, I have no issue with it at all.