Was this 1st Edition AD&D? What was your guy like in terms of stats?
I remember trying to extrapolate a Sage PC class from the materials on NPC sages in the DMG 1st Edition...never quite got that figured out, but I still like the idea of playing a sage.
Something like a diviner/bard might be more playable as a sage rather than playing an expert, but still...
To further clarify...I'm talking the DMG 3.0/3.5 NPC class, not the Unearthed Arcana class [although for the purposes of playing a highly skilled nontraditional PC, the latter is very interesting].
If I ever start a campaign from scratch again, I will require players to take two levels or so in one of the NPC classes before they can qualify for a normal class. I like low-power games. This way, the normal classes become almost like prestige classes. Got the idea from Dragon magazine about two years ago, in an issue about George R. R. Martin.
In 1E, we had our own class called "Mundane" which was essentially the same as the current Expert class. We had one or two PCs take some levels in it to get the skill points (also had our own skill system since 1E didn't really have one).
Didn't really like it. I would boost his skill points to rogue levels and let him have feats as a fighter (number, he would not be limited to a list). That way he would be on par with a rogue, but the player would have the freedom to make what he wanted.
Not yet, but a guy I know is working on the Quintessential Expert, and considering I really liked what he did with the Aristocrat I'm eagerly looking forward to it.