This would do nothing. The best layout would be found to best suit each jobs strengths and everone(read: alot of people) would just copy and use it. Nothing changed, most monks you see running around would be the same cookie cutter monk etc. SE foresaw this and decided to put a system in the game with no customizability to this degree and why shouldnt they? Why waste develeopment resources on a system they know players will break down into a few builds and trivialise.