You can give linked full-random, elemental-only and sorcery-only randoms.
7.12.1 #magicskill
Gives a magic skill to the active monster. The
path must be a number from Table 9 and level
should be a number from 1 to 10. If the monster
already has this magic skill then the old level will
be replaced by the new one, unless it is a
random skill.
End of Table 9:
50 Random
51 Elemental
52 Sorcery
Male mages could have
#magicskill 51 2
#magicskill 50 1
and female mages
#magicskill 52 2
#magicskill 50 1
1/32 chance of level 3 path, all path combinations are available and all mages can do something worthwhile.