Originally Posted by jamieth
with Greater Multi-Weapon Fighting you have two attacks from each of them, for a total of 10.
Just thought I'd note that you are wrong here. Improved two weapon fighting gives you two attacks with each weapon. Greater multiweapon fighting give you three attacks with each weapon. As such you would have 21 attacks, not 16.
Edit: Also, while it wouldn't show up until epic there is Perfect Multiweapon Fighting (from EL) which lets you get off hand attack for every attack (from itterative attack bonuses) you get with the main hand, meaning the magical girl would have 26 attacks.
Also more relevant to the builds as they level up is Multidexterity (from MM2) which gets rid of penalties for using off-hands for anything. This would remove the -4 penalty to attack rolls suffered from wielding multiple weapons.
Alternatively you could go with Oversized Two-Weapon fighting which makes one-handed weapons count as light weapons for the penalty of using them in the off hand.