After looking at the Kemmlerian Necromancy Sponsored Magic entry I felt like you could use the same setup to reflect other types of magical traditions/lineages with similar packages for people who are already wizards to buy. As I am an avid fan of summoner style characters, my first impulse was to take that towards a summoner tradition.
Depending on how you want to include such characters in a given campgain you could fill them out story-wise in different manners, for now however I'm just focusing on the mechanical aspects of the build.
Summoner ( -2 Refresh ): Provides a +1 Control +1 Complexity specialization in Summoning/Binding magic, stacking with other specializations. Can cast Summoning/Binding style spells with evocation speed/methods, using their Thaumaturgy control score. ( Don't forget that 'Binding' a person is a Law Violation... ) If a point of debt is incurred for the casting they can use their Summoning/Binding Control score with other elements/methods of evocation, to reflect a rapid if expensive pact/bargain with some sort of summoned entity to provide the effect they throw in the spell.