In turn base I love choice. This game gives you a ton, having mixed classes, means even more.

Battlemage - Mixed Fighter and Magician, always great with options.

Wizard - Pure, most schools learned. Magicians in TB games always have the most choice.

Madora - I get her up to a point I can use a bow with her, so she becomes a fighter/ranger, allowing her to use all the custom arrows really adds to what she can do move to move.

Jahan - Like the wizard main I build. Learns most schools has lots of options.

3 out of 4 will have Teleport to really mess with the baddies.

I work the two wizards into Glass Cannons, focus is Int, Cons and Speed, this way they get at least two pops per round. Getting 16+ AP a round at level 6'ish is pretty powerful.