Power attack is always a good feat for a melee character. Assuming shield is one of your spells known then there's no excuse not to use a two handed weapon, preferably one with reach.
Your spell list is going to be another big decision, I'd go for the following:
1-shield, silent image, nervesketter, swift expeditous retreat,
2-invisibility, wraithstrike, detect thoughts, resist energy (assuming you didn't take this as a duskblade spell)
3-haste, greater magic weapon, magic circle against evil
4-polymorph, greater mirror image,
5-telekenisis, dismissal (let's you qualify for sacred exorcist if you want divine feats like divine might)
Lots of swift/immediate action spells assuming you take all 5 levels of abjurant champion