Here is an idea, make off hand equipment for various purposes.
What I would like to see is a variety of equipment for the off hand battle system linked with abilities for the type of gear. An example would be for a healer one would have the options of <A: a, b> <B: c, d> <C: e, f, g> <D: h, i, j>, each being something different that has 2 or three special abilities depending on the level of the item, the equipment being interchangeable and in the case of a change of equipment the abilities would be active or inactive. and of course there would be similar objects for the tanks, melee dps, ranged dps and magic dps.
I don't think this would cause too many problems to be able to switch them in instanced areas like dungeons and would add a dynamic element to the gameplay of using the right off hand equipment for the job.
In the comments, aside from general feedback and opinions I am looking for Four good options for each:
Healer A. B. C. D.
Tanks E. F. G. H.
Ranged DPS I. J. K. L.
Melee DPS M. N. O. P.
Disciples of Magic DPS Q. R. S. T.
You don't necessarily need to come up with all for in the same Role just state one of the corresponding letters; if so desired, use your creativity to come up with abilities that you think would be useful but also must be a function of the stated piece of off hand equipment for that role.
(Example: Healer <A- Satchel of Strange Pebbles: a. Divining Stone "Heals party members within a radius of 5 yalms 20% of damage inflicted with stone mastery for 10 seconds."
b. Exchange "Designate a party member within 30y that will absorb healer's HP over 10 seconds at a rate of 15% from total." >
Please also give a brief explanation of the piece of equipment itself, you don't necessarily need to explain the abilities themselves. In this case, A satchel of strange pebbles in the context of a healer may represent the energies in stones, crystals and minerals themselves which are used in order to cleanse the mind and body of themselves and their patients.
Relationship to game: The main damage dealing spell of the white mage is Stone, It seems only fitting for the collection of unusual specimen of aetheric properties in order to purify the taint. The successful practice of purification using a variety of stones has lead healers abroad to seek and collect stones of aetheric properties. (In this particular case it may be that because stone can only be cast by a conjurer or white mage that if a scholar or astrologian were to equip the Satchel of strange pebbles for their off hand that they would get only the ability b. Exchange Now obviously I have not done a very good job of creating an ability that would be available to all three classes, but you get the idea.)
Have fun and take care!