Actualy I see lux fare the best out of any AP.
Brush checking abilities, shield support, a pretty nice snare and that ult is good at capture disrupts.

I would put her on the top of the list over cass or swain. Utility is more important than damage, but she still can crank that out as well.

Hell, I've even gone AD lux for the lulz and done pretty well =P

Ryze, cassio, Kassadin, fizz, swain, Ahri, Teemo, Malzahar are imo the best ones. I think Anivia is way better than many people think.

I wanna give Veigar some credit too, people cluster a lot at top, and his dark matter and ring stun are pretty nice. Just gotta make sure to enter the fight late so you don't get smushed fast.

Though she's technically a support, Lulu is a fantastic caster on Dominion. Amazing Utility, and the tanky Mpen build works wonders on her.

Viktor

Seriously, he has everything needed to just crush in Dom.

Lux is one of the worst dominion champs. I dodge when I have one on team zzz so bad and people are bad at her. I can't beleive people are saying she belongs in the class of the Lulu's, Ahris, Cass, and Kass.