Chronomancers take it hit without many low casting number spells to start with, and a lack of travel or direct damage spells in their primary.
I'd go with:
Crumble (10) Making doors and making pot holes in bridges where they don't belong
Decay (12) Disarming that soldier heading your way
Fast Act ( 8 ) When you have nothing better to cast, going first never hurts, and scores you 10Xp
Elemental Bolt (14) Sure you'll suck at casting it until you upgrade it, but it is the most powerful attack in the game
Mind Control (14) Nothing ruins a wizards day when his treasure toting thug decides to work for the other Wixard
Raise Zombie (10) Extra soldier, 10XP per casting
Leap (12) Probably one of the best powers in the game for moving treasures around
Animal Companion (12) Bears scare people, and they don't cost you any Gold Crowns
If you don't want to go the Animal Companion route
Absorb Knowledge (12) You don't have to ever dump any upgrades into it and it's a 40% chance per sceanrio for 50 additional XP