Well, I'm not really positioning this case to be decided on "fairness."
What I am trying to address is the nature of Enchantment spells, as they have been manifested/scripted by the NWN2 engine and developers.
Are there other Enchantment spells, like the Mass line of spells, that also affect the Caster? Or, is it what I'd personally like to think is an oversight in the mechanics, that make Confusion and Chaos a "physical" sphere of Effect, like a Fireball, and not as it sees more appropriately interpreted as a mind-to-mind type of magic, immaterial.
The Spells themselves clearly state they are directed towards "targets," and it is with great doubt that I'd expect a mage to target themselves.
Now to be fair

, IF the spell was called Rune of Confusion, or Barrier of Confusion, or Field of Compulsion, or anything that described and/or implied a physical creation that could come into contact with the Caster, I'd be happy to accept a Caster requiring a save against an "entity" of Confusion, that manifests from the caster but exists in form.
But none of that is described AT ALL with the 2 spells in question. It seems like a simple oversight in the development of these spells.
And again, if Confusion and Chaos affect the caster, then why not also have the Mass line of spells also affect the caster?
I'm open for hearing the argument that making Confusion and Chaos NOT affect the caster, is simply OP. But I'm not hearing that argument defined...yet.
Cheers.