Option 1.

We could just allow tinkers to forge "accessories" - rings, amulets, magic wands, magic scroll blanks, etc.

Also, allow enchanters to lock spells into items (same way blade spell are locking now).
So, ring of BOA - ring with locked blessing of agility spell onto.
Wand of MM - wand with magic missiles spell.
Beside power, there should number of charges it could be used. It should to raise with Caster Levels, I guess.
When discharged:
a) lock disappeared and you may lock any new spell.
b) lock stay inative, you must ask some chanter to restore lock power.

Option 2.

Add category T in each guild and allow to train some crafting skills specific for each guild (you may leave tinkers and chanters as is).

So, some guild could forge, some could give power to existing items.


Limiting number of owned items may be in effect.
Looting should be allowed, but by same rules.

Say, each item is taking own slot in inventory, so, if you are given with new item with same kind, you should be warned and questioned which should be dropped to the ground.

Of course, it may be unlimited and one could have million items in the bag of holding and switch them constantly :).