I don't think the dev team has a natural instinct for streamlining FFXIV, the only elements that are streamlined are either, over streamlined (the anima system) or stolen from wow (instant mounts). MMO's are hard to design for because the community has the end all say if the game is fun or not, if the community isn't willing to sit down and use the enmity system to ensure everyone doing max damage then its not going to happen and the developers need to abandon it immediately.
I think they should just scrap left and right bonuses to be honest since that way they can still keep the back attack weapon skills vital to have a tank without sacrificing unrealistic expectations of perfect tanking...