What I did is I took elements of the characters (in this case owl theme and adventuring theme, as seen with a grappling hook to yknow tarazan around) and a pattern from the extended zodiacs symbols for the caste (all/most indigo symbols have an arrow, all/most purple signs are open with a loop somewhere in them) and applied them together to form these signs!
...they turned out a lil meh on the sprites but im proud of them :p