AD&D added the illusionist (at least I don't recall the illusionist being in OD&D) but it took 2E , published in 1989, to round out the specialist mages. Those other specialists included the necromancer, the evoker, the diviner, and so on.
In many ways, Avalon Hill beat TSR to the punch. Magic Realm was released in 1978, and 10 of its 16 characters have access to different kinds of magic.
There are 8 types of magic in Magic Realm:
I - white magic (divine), cast by the Pilgrim (read Cleric) and White Knight (nee Paladin)
II - grey magic (natural), cast by the Wizard and Druid
III - gold magic (faerie), cast by the Elf and Woodsgirl
IV - purple magic (elemental), cast by the Sorcerer
V - black magic (infernal), cast by the Witch and Witch King (read Warlock)
VI - conjurations
VII - good luck knacks
VIII - malicious tricks
The Magician has access to various types of magic, but he needs different magic items (which supplied him with the mana he needs) in order to come into his own.
I like the approach that Magic Realm uses, as it makes the mechanics for the clerics and the wizards the same, by making white magic just one of the several magic types.
In addition, each character has access to unique kinds of magic, (and is restricted from using others) which is very similar to the specialist approach in 2E.