Customization is not the problem, ppl just fail to realize that this game and every other mmo who labels itself as rpg nowdays is designed in way where is is this one treshhold caled dps check. No skill/creativity/thinking is ever required to do active fighting. All the boss fights are desingned in rat labyrinth fashion, you just run in every direction until you find the food. You can argue that executing rotation is "da skill", but even that aspect is made cookie cutter aplication for EVERY single fight that happens, happened and will be introduces in future.
They way i feel the fighting is with hitting and recievieng if you boil it down is no different then juggling beads on abacus back and forth. In a way to me active combat healing class is mysterry to this day, there realy is no logical concept behind action of 'to be healed in active combat'. I think that healing class as part of holy trinity in the concepts it was concieved will die when humanity will adopt real virtual reality gaming as it is depicted in SAO. Healers in essence are just potions you spamed when you played diablo 2. Even if i look through roleplayers fantasy eyes, even then I cannot think of any logicaly acceptable reason how healer as he is in videogames could possibly function.

You can cry all you want about customization, but as long as there will be timed dps checks and every single job boiled down to bare bone functioning (all the fancy animations and graphical shinies removed) will be identical how they work and what they do, ppl will look past they shinies and will look for raw numbers to operate with. As those the real thing that matter.