I believe some revamps that would be nice to the armoury system without taking away from it, because I believe that yes, it makes the game unique from most other MMOs, but it seriously needs alot of work so it doesn't make every class a generic Cure spammer.

Slight Mod to Current Abilities and Spells:
I believe alot of abilities and spells for other classes should cost more when using them cross-class. Not all of them, but like drain-styled spells from THM, or elemental spells that lower elemental defense from CON, stuff like that. Make you take more strategy in setting up your character without ruining the system. Also make classes less of just "what you're going to learn" and alittle more "what you're going to use".

But, spells like Cure remain the same cost. Yes, every class using cure seems abit redundant, but maybe Cure II cost more, so you won't see people cross-classing a higher tier.

Additional Abilities and Spells that are Class-specific:
Each class should get a few new abilities for each 10 ranks, whether one class gets it at 2, 12, 22, etc., and another at 5, 15, 25,...

These abilities being completely unusable outside their class. The ability stat of "Requires: Class or Discipline" is already programmed in, so would just be implementing that alittle bit more. These abilities must be complementary to what the class does though, such as CON getting "Your fire spells do more damage for a short time." or "Your Cure spells gain a +10% bonus to amount healed for a short time." or even a weaponskill doing regular damage and "Lowers target's defense against a random element or your weapon's current element. Depends on weapon equipped."

Of course, same goes for spells, introducing a few new spells that are either class-specific or restricted to "Disciples of Magic only".