Maybe you could alter that idea the following way...
By introducing a rewarding system simmilar to the treasure hunt with the maps now in game but for mage players...
Make it extremely unlikely (a very low encounter ratio) for a mage player to find a description of a generic ritual while reading in the library
(In comparison to the fishing for treasure maps).
The things generic about the rituals should be:
Yield of "power" (the reward) ,
Objects needed to perform the ritual,
required initial skill to perform the ritual (As you need better digging/mining for harder treasure maps?),
type of ritual ("good" "evil" "neutral"),
difficulties that might occur during the ritual ( i. e skeletons are being raised because something goes wrong while performing a bad ritual,),
and also make it that the mage has to find a particular place on the island suitable for the ritual (as you have to find the spot you have to dig out your treasure at); maybe even have it set that the ritual needs a special daytime to be performed (an evil ritual in the middle of the night; some at dawn etc.)
I will try to write down some examples so you know what I mean:
You can add difficulties like "needs two/three/four mages to be performed" to make it a "social" activity and opportunity for roleplay and teaching"Small evil ritual of the skull"
Yield of power (small like a little immediate mana boost 1/4 of the mana bar?);
Skill to perform (commotio, pervestagio w/e magic skills apply I dont know that I dont play a mage character to a "beginner" extend)
Things needed: skull, lambleg, ink, ornate dagger
Type of ritual: Evil
Difficulties: A single skeleton might be summoned and will attack the caster when he does something wrong; he might actualy LOOSE mana by performing the ritual wrong; an astral voice starts to laugh at him and his inferior understanding of the mana;
(somebody complained about the only way to raise ones magic skills is by spamming spells around, this way rp would be encouraged (interaction with other mages, maybe your master witnessing you perform a lesser ritual... I dont know).
How about it?
(Maybe (once the other types of magic are introduced) a simmilar system for priests and bards too)