Scaling of abilities to a player's level is not a step in the right direction.

[Charismatic]

I dont know, its really rare to see a mage class in any game with only 15 abilities total. Its also pretty rare to see amage class which uses all its abilities at once, usually they take a wide variety of skills, and use the ones that apply the most.

Which is fine and good because you won't have only 15 abilities total. You'll have cross class abilities... such as nukes and CC from other classes whose effectiveness also scales with level. Does this mean you'll need to level more than one class to level effectively? Maybe.
But it is already like that even now... though to a less extreme degree.