Alright, I'll probably end up going magic then. I like casters better anyway.
Should I bother getting/maxing the elemental charms? Also I'm assuming since Oboro's only really have support-y skills for magic, I'd be using the magic ninja skills? (Sorry I'm super noob at the class.) Also what about Swirling Petals? Would that be worth it to get or not at all, since it goes off of dex AND agi?
since you only have self buff for oboro's magic, you will mostly rely on ninja magic skills and synergy them with Charms. Most definite charm you would want is Fire Charm. Earth Charm is something you can choose between getting it and not getting it. If you want to somewhat hybrid with either Kunai Explosion or Swirling Petal, Earth Charm can be usefull since it gives 135% increase in your physical attack skills(you want to summon only 9 charms because 10 charm will overwrite your Kunai Explosion to Earth property.)
This is example of Oboro's skill tree. unless you want to invest skill points from oboro into Ninja, you wont be able to get all the skill you want from ninja.
Skill Tree
Blazing shield is your main AoE skill since it hits 2~3k per hit(with mild gear set up) which makes it 30k total of dmg. and 15k~20k from exploding dragon. if you can gear up a lil bit(spend bit more than a eden gear) you can expect decent dmg from oboro.