2e and 3e wizards/magic users were gods, not because they were dps cannons, but the fact that they were the swiss-army-knife class. It's their versatility to adapt to situations by memorizing the right spells made them powerful and therefore fun to play. The downside of course were their HP and the need to rest and memorize.
In BG2 and TOB, with meta-spells like Spell Sequencers, Spell triggers and Contingency, you often find tanking (and sometimes melee classes) irrelevant, as magic users could fire off a combo of deadly spells within a very short period of time.