Ok, so I should elaborate on that:
Rituals will be what you do when you need lots of power and must accumulate it over time, because you simply don't have enough energy to cast it as a spell.
Spells are basically unchanged.
Spontaneous magic is changed. This is what I outlined above: You describe what you want to do, and how much power you put into it, and then you'll see what happens. How close you come to your intended effect will depend on how well you estimated the required power.
