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Here's a nice legal way to get more spellcasting per round: Cohort or allies who are Spellthieves. (If the Master Spellthief feat is allowed, than a Wizard with one level of Spellthief qualifies, but then he might prefer to cast his own spells.)
Basic idea: Spellthief 'steals' (with a touch) whatever spell you want to cast twice, and then casts it on his turn. Doubles your firepower.
It's just one spell over and over again, but if we're bringing cohorts/allies, you could have them bull rush the opponent into and out of a hallow or unhallow.
Ok, so that would never work in reality, but it's a cool idea, no?
Factotums from Dungeonscape get an ability at 8th level called Cunning Surge, which lets them spend three inspiration points and get another standard action.
There's a feat from the WotC site that gives you a number of additional inspiration points equal to the number of times you have taken the feat.
This lets you get loads of extra actions. Now the only problem is keeping your wands of Charm Monster and Charm Person charged up.