I don't like Wizards at all.
Aine - may or may not be a tribute to Annie Lennox. While the latter pursued a solo career, Aine should be a secondary hero as she's perfect for it.
Astral - has the spell that never works.
Cyra - is pretty good provided the army is substantial enough to overwhelm. Diplomacy is always welcome. Gets my vote but mainly as a tribute to Terek.
Daremyth - I'm still not convinced Fortune special has any good use at all, and she has Intelligence which for a Wizard is kinda superfluous.
Halon - Mysticism special is neat.
Serena - I'm not even gonna say it anymore. I loved her diary, though.
Solmyr - Yeah, not bad. Still, Chain Lightning isn't all that good. For one thing, AI loves War Machines. For another thing, the final two (three) bounces are not going to help you much. Meteor Shower is better almost all the time. And unless you purposely under-staff your army you'll rarely be able to cast it when fighting wandering stacks.
IMO Solmyr is a one-trick pony who is good for rushing but otherwise better off as a secondary.
Theodorus - Quite the might imposer with Ballistics and a creature special. A pretty interesting choice, Ballistics certainly helps keeping your expensive army alive. (Arch) Magi are already damn good units by themselves but any combat boost is a blessing for a Wiz.