Personally, I would have liked to see a Stat distribution before I make this opinion, but I'll throw in my two cents.
Moxie is not a risk/reward ability. There is zero risk in running Moxie. The only bad thing is that if you have shit attack stat, to which you probably shouldn't be running a physically offensive Pokemon in the first place. Also, with a Bug / Psychic typing, this thing will most likely not be physical.
No Guard is tempting, mainly because there are two perspectives to this. On the one hand, all of your moves hit, but this also means that all of the opposing moves hit (Stone Edge). However, I don't think that this is the best route to go, mainly because the insurance of being able to hit all of your moves doesn't highlight a risky situation in my opinion.
Regenerator - No. There is no risk when you have leeway of switching out and regaining HP based on a crap mistake or hax.
Simple is an ability that really is dependent on the Pokemon's Move Pool. For example, if this Pokemon got Quiver Dance, this Pokemon would be SOOOOOOO broken. I'm going to lean towards a no on this one, mainly because I want to have the option of Quiver Dance available.
Illusion is a really cool idea, and is definitely my first choice of abilities, but I think that it highlights a different risky situation than the one that is desired for CAP. Illusion is mainly dependent on the opponent, rather than the user. However, if this comes in the final decision, I will probably be leaning towards this, mainly because Illusion is a cool ability that needs to be spread a bit more.
Flare Boost is probably the #2 in my book. An SpA boost (and the possibility of Quiver Dance) at the cost of Burn Recoil and an SR weakness. Not to mention it might have to predict WoW in order to be useful? Sounds like a cool idea.