Tom,
I could easily see a way around some of the power level issues that relate to concentration/control/precision. For instance, lets say that I'm facing a group of ruffians. Instead of casting a massive fireball, what if instead I use my fire whip and simply lop off all their heads, Target size 1, Duration 1, Effect 4.
However, it would require a lot more control to make that thin fire whip, so instead of an easy 1 generic fireball, it is an inherently more difficult spell of say 2.
