These are the soldiers and spell lists I started each of them with. You can't really go wrong when selecting these, istm, as you can base strategies on whatever you come up with. I'd go for a few missile troops, generally, though. My summoner warband suffers coz I didn't have any cultist-with-crossbow minis.
Also, movement type spells like Telekinesis and Leap might not sound very exciting, but we've found them to be the most useful.
My pacifist Thaumaturge band, just pretends to be pacifist, and then Blinding Lights you in the back when you're not looking, so you can't look. It started off with all Archers, but now I have some rangers, knights and templars.
These guys, from the cult of the Orange Simca, are a bit more up front about their belligerence. They could do with some ranged attack soldiers, but I'm waiting to get my hands on the Northstar plastic Frostgrave Cultists box.