My idea is going beyond the current materia system and go to untradeable type materia you get the drop from some dungeon or fate boss and gives a basis enhancement of Freecast trait for 1% as an example so you can only get one to prevent stacking and overpower the game. Then your grand company housing can set up a materia systhesis shop like the machine you see around the goblin and its a rank base type leveling for crafter's to unlock better abilities to where you can take materia out of equipment without destroying by payment of company seal's. Then that untradeable materia you got can then be processed into a unique untradeable green item and then have to attach it to an item to spiritbond and maybe some other stuff to be able to create a purple relic type materia. Allot more details for this would be needed of course and this is attended for furture content in mind something to give player's more to do with the current materia system imo please feel free to add anything if you like the idea im sure some won't.