I definitely agree w/ CLOVENHOOF, see the post up above.
In terms of RPG. the Hyborians are the most versatile race and hence they have fewer hang-ups.
I always liked the concept of the Pictish Sorceror. Although no where near as powerful as Xaltotum, the Pictish Sorceror's were numerous, cunning, and able to conjure evil horrors out of their massive forests, whether it was a swamp demon, chakan, sabre-tooth-tiger, or giant serpent.
I have been tweaking with the magic system and decided to give the Pictish/ Ligurean (see Thunder RIver) access to the spells "Shapeshift" and "BlackPlague" through nature magic. I just love the concept of these wicked men brewing a plague cloud over an Aquilonian fort.
I have decided to give them sacred groves where they can regain powerpoints, conjure hideous creatures, and sacrifice numerous captives.
I have to say that although the Pictish Sorcerors not a Preferred class, I think it should be, seeing how prominently they figured in Howards writing.
Likewise w/ Zamorians, too.
When you read the CONAN THE BARBARIAN comic books, there are a lot of stories involving Pictish sorcerors (somewhere around episode #160-170, maybe???).
The main thing that I would do with Pictish Sorcerors is cap their Scholar level at maybe 14th or 16th, although not as powerful as other sorcerors, I think they win at the numbers game since every clan (600-1000 tribesman) has at least one it seems, where as in a large hyborian town of 5-10k people you MIGHT have a sorceror.
I think you could allow a Preferred Class for the picts and Scholar, if you tweak it just right; namely no access to eastern, cosmic, or other esoteric magics. One of their bonus feats would have to spent on a Wilderness or Combat feat, no access to Eastern feats like meditation.
THe Pictish Scholar-Barbarian, is one of the formost opponents in Conan.
I absolutely love the cruel and wanton nature of their society and how they view the civilized folks.
Just my two cents.