can you give specific examples of ones you dont like and why?
I can give you counterexamples of how I'd break down the points cost of the powers. Perhaps that would be more helpful.
Seelie magic:
Sponsor debt - freebie
Element for Evocation with summer-like feel - 1 point
Thaumaturgy along summers themes - 1 point
partial catch for unseelie fae - 1 point
Biomancy at speed and methods of evocation - 1 point
Notice that interpreted this way, the power rebate actually makes sense, rather than just giving away points for nothing. Its also fairly in line with non-sponsored magic costs, although still a little more powerful.
Unseelie magic:
Sponsor debt - freebie
Element for Evocation with winter-like feel - 1 point
Thaumaturgy along winters themes - 1 point
partial catch for seelie fae - 1 point
Entropomancy at speeds and methods of evocation - 1 point
Same story as above
Kemmlerian Necromancy:
Sponsor debt - freebie
+1 control/complexity in necromancy - 1 point
necromantic and! psychomantic effects at speed and methods of evocation - 1 point
control bonuses from necromancy can be used in evocations - freebie!
The control bonuses for necromancy make this one much more powerful and easily abusable than the other sponsored magics. My guess is that the developers put in in there because it makes sense to let the thaumaturgy bonuses be used with the 'speed and methods of evocation' powers that come with the ability, but it created a broken ability by accident. OR, they gave this ability more power because it practically requires lawbreaker to use. +1 control/complexity is equivalent to a point of refinement. Necromantic and psychomantic effects at speed of evocation is a bit stronger than other sponsored magics, but oh well.
Hellfire:
Sponsor debt - freebie
fire element for channeling - 1 point
diabolism, entropomancy, and disruption for ritual - 1 point!
+1 power/complexity for all spells that try to inflict stress or consequences - 2 points
This one is pretty standard. The multiple areas of thaumaturgy are pretty strong, but it makes sense when you think of those areas as being thematically linked to the power. Along those lines, Entropomancy, for example, should not work with the power unless you use it with a hellfirish theme. +1 power/complexity is like a point of refinement, but its broad enough that its well worth the two points it cost. Maybe even a bit of a steal