I think you should try to expand this magic stuff, it would greatly benefit the mod.
But it should not be in a standard way, it should be darker and edgier, as befits this pretty serious mod. You should only get the power to cast spells by sacrificing virgins. Rename Long Dagger to Sacrificial Dagger for this, and let players check if they are virgin or not. But being virgin should have benefits, since being hunted by mages would frighten many players. This is also realistic, look at medieval literature (at least they could get access to unicorns, but I'm derailing). Mundane fighters should have the power to carry virgins around and restrain them so their teams spellcaster can stab them for a roundchanging spell.
But the real important things is, and that's really important, magic should not be accessible to just anyone. It should be rare and powerful (a single mortal should be peeing his pants when facing a mage). All other ways would just totally ruin it.
That said, only two types of characters should be able to become spellcasters.
The chars of the developers - since they are somehow touched by the gods that created this world. Maybe this sacrificial business doesn't apply to them, or they can sacrifice themselves because of that.
Characters from a sorcerous bloodline. This means, they must have played at least one generation as a mage before anyone but a clairvoyant could predict that spellcasting would be added. Lorewise, these characters (or their ancestors) have not gained their magic through the gods, but through obsessive determination. They lived through a period when the magic left the world, unable to lift even common weapons as their pursuit had weakened their bodies and suffered greatly at the hands of black plated knights and everyone else, but they passed their powers on to their children and grandchilder, who realize their potential now the magic comes back. It's just fair to reward these players. As it happens, my first char (way before retirement was even added) was a sorceress, with quarterstaff, dress or robe, and sacrificial dagger. I still have a masterwork quarterstaff because of that. There was also someone playing a wizard.
Since it would be really only a few people, and it would quite hard to get the ingredients for spellcasting, it could be made more powerful without breaking the mod as it has in many other games.
Just think how much fun it would be to read stuff like "Help! My character suddenly was a goat. How can I fix it?" (*) and answer "Find the mage that did it to you and convince him to lift the spell".
edit: (*) Since there are goatmodels out there a permanent turn into goat spell is obvious.