So, Backup character... / Help me build a Battle Sorcerer

[dascarletm]

Okay, so in my other post there is a good chance my character may die, http://www.giantitp.com/forums/showthread.php?t=278953. I'm going to be rolling up a backup just in case, and a character I've always wanted to play is a Battle Sorcerer type: (?'s I'm unsure of, and ___ i don't know what I should do)

Here is my current build Idea:

Human, Battle Sorcerer 7 / Abjurant Champion 5 / Battle Sorcerer 8 (maybe a level of archmage?): (UA Variant) and Spontaneous Metamagic from PHB2

Feats: 1. Extend Spell, Combat Casting 3. ____ 6. Leadership? (battle campaign, and we can customize followers heavily) 9. Quicken Spell 12. Persist Spell 15. ____ 18. ____

Should I drop in some Cleave, or other combat type feats? What about mounted combat?

Spells:
0: Detect Magic, Resistance, Light, Prestidigitation, Detect Poison, Read Magic, Arcane Mark, Message
1: Fist of Stone, True Strike, Blade of Blood, Shield
2: Mirror Image, Whirling Blade, Blur?, ______
3: Phantom Steed, Vampiric Touch?, Greater Mighty Wallop
4: Greater Luminous Armor, Orb of Force, Dimension Door
5: Greater Blink, Arcane Fusion, Undying Vigor of the Dragonlords
6: Greater Heroism, Antimagic Field?
7: Greater Teleport, Justice of the Wyrm Kings?
8: Greater Shadow Evocation, Protection from Spells?(or Greater Celerity?)
9: Shades, Time Stop

Items:
What should I look for?

What do you all think? Now the DM is cool with optimization, but if it is too cheesy he may be hesitant. If you want to gouda it up feel free, I may just not use it.

The keypoints are that I can hit a group decently well with whirling blade, I’m pretty tankey with all that armor, nice single target damage, and I should have really good mobility with the steed.