As already said in this thread, Marid wasn't originally a water spirit. It was made that way in D&D, probably because "mare" and "marid" sound similar.
This mod is forming up quite nicely. Just in case I seem to be complaining all the time, I only speak up when I disagree with something. I like everything I haven't mentioned.
So, the Marid is a really powerful, evil Djinn, an Effrit is an evil Djinn that is not so powerful as a Marid but still very powerful.
Next lower is the Sila and least powerful the Ghul - and those are only the evil.
Dao has nothing at all to do with Djinns.
I think Djinns would make good unique summons, sadly 10089 is not modable. I'd say it could best be an air Summon with secondary-fire that has fire, air, some earth and sometimes water or astral magic (like 3/3/1/0/0 plus 200% random)
Other mythological creatures of this area are the giant bird Roc and the feary-like Peri.