How much would the Refresh cost be to add a new area of evothaum to an existing Sponsored Magic?
For example, Leanansidhe can clearly do Transformation/Disruption (or Biomancy) at evocation speeds, but Unseelie Magic doesn't let you do that. Would adding Transform/Disrupt as-evocation be worth [-1] Refresh?
And what about adding a field of evothaum to a non-Sponsored spellcaster (maybe the Gatekeeper can do Worldwalking as-evocation, or the Merlin can do wards as-evocation)?
Finally, what about a character that can do ALL thaumaturgy as-evocation (barring stuff directly opposing its high concept) - Mab might have this one.