I'd like to see a codification of what sort of magic exists, first. I know it's a remnant of the "D&D as fantasy toolkit" approach, but I wouldn't mind some top-down perspective of cosmology and magic in the PHB.
Arcane magic as the remnant of primordial creation, bound by symbolic gestures and materials, reflective of the chaos that surrounds creation.
Divine magic is accessed by rituals and prayers, that speak to the nature of the gods and entities invoked. The gods are the oppositional force to the primordials, binding and fixing creation into forms. These forms can be altered and perfected by divine magic.
(Yes, I'd like to see D&DN focus on the law-chaos axis, with the gods as the lawful side and the primordials as the embodiments of chaos. Combine the best of OD&D and 4e, and throw the great wheel back in too!)
So, I'd like to see:
Wizards as masters of invoking arcane energies. (Not generalists, focused on knowledge abilities and blowing stuff up).
Priests as masters of divine rituals. (General healing abilities, specific abilities based on god/philosphy).
Fighter.
Thief.
Bard. (Social skills + illusion/enchantment arcane magic).
Paladin.
Some other classes, but none that introduce a type of ability that isn't codified within the description of the cosmology.
