Look at this great thread and see what you can use: http://brilliantgameologists.com/boards/index.php?topic=9876.0
Halruuan Elder 1 and/or Metaphysical Spell Shaper 3 seem best for your purposes. The first has Circle Magic, the other has completely free metamagic, if you have a level of Binder (which you do!).
Already did that CantripN (I even have it bookmarked).
It's a great thread with very solid ideas, however. There shall be no prestige class dipping pour moi. As it stands I am stuck with my current build. All in all though I am happy with it. It might not be as uber as the true Mailman build but it's still pretty solid.
Cheers
Volf
