[@RaeoftheLight]
Yay! Hi Rae.

It's really a just comparative thing. 
But your right, a suggested guideline example would be good. 
I'll work on that soon.

An E rank can still be flashy or a strong power but if it comes up against a B rank power (or wizard with B rank) he will probably overcome it.

I really don't want to limit people's imagination or ideas with the ranking system but you need to accept that some people will be better in certain area's.
Ideally you should try imaging the absolute height of your power and also the simplest foundations of it and move between there.
But at the same time I wouldn't complain if you used the same 4 attack spells that just slowly became stronger.

:/ hope that helped.
I'll have examples up soon ;)