Actually, I would give Molly the Glamours power and one stunt that increased her facility with veils using the power, alongside her normal spell casting. I would give it to her for the same reason that you'd give Injun Joe True Shapeshifting- it's easier to model like that.
True, but in this case you'd be using a different set of rules. Molly WOULD take stress from using her glamours, so refinements would be more realistic than the glamours power.
Of course, you could always give evocation and glamours, then a stunt to use them in combanation and provide a discount on that stunt with a caveat that it counts as evocation and thus causes stress. Again though, this pushes back into the 'just as complicated' catagory.
Personally, I'd just go with the 'powers as rotes' method - create a spell possible through refinements and focii and turn it into a rote spell. Injun Joe would have a powerful rote that gives him true shapeshifting, while Molly has a rote that gives her glamours for the scene. This way, they have powerful abilities that last till the end of the scene rather than a one shot glass cannon like Dresden.
As a disclaimer: I probably wouldn't even allow these type of spells as evocation without it being a rote spell, and probably require an aspect like Molly or Injun Joe use.