No, I'm saying that if you are just going to use the power 90%+ for the attack/block/maneuver that evocation can already do, and use it to 'make' relatively normal weapons that you can hand out to your friends (some sort of thaumaturgy at evocation speeds) then the power is fine as just 'sponsored magic'.
So, the parts of the power that you can't do with that power already should be the ones you spend all the time and rules effort on.
Technically, evocation is really a power that allows you to attack, block, or maneuver and interacts with the action economy, certain skills, etc in certain ways. And what sponsored magic does is to provide a 'story hook' that describe the theme of your attacks, blocks, and maneuvers.
For example, the the 'reality marble' just an excuse to have fight where you can throw huge gouts of fire at each other and not damage the countryside? May be best implemented as a genre convention of the game, not a specific power.
Or can you do other things with it?
Examples I can think of:
Store stuff in it. even large things, like, say boats, automobiles, or minions and then take them out when you need them.
Act as a barrier to escape, so that once someone is in it, they have to deal with you?
Act as a maneuver generation engine, that doesn't have the stress limitations of evocation (i.e. something like the 'incite effect' power)?
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Now that I think of it, writing up 'magical sponsor' as a power which adds onto magical powers and replaces 'sponsored magic' may help clean up the rules a little bit. This also allows you have sponsors which are more powerful (and costs points) or sponsors that suck somehow (and give you back points).
This also removes the odd cost difference of sponsored magic when you do or don't already have other magic powers.