Except it isn't broken, the system works just fine. If it were truly broken then you would have far more people failing at simple "don't stand in me" mechanics. Busier fights like Titan and Midgardsormr would be next to impossible. As it stands, most people are only getting hit because they lack spacial awareness and decent reflexes. The telegraph shows you were not to stand, the castbar shows you how long you have to get out of the way. It's not complicated. Players who can't comprehend that would probably still fail even if the animation and castbar lined up better simply because they aren't paying attention to obvious cues.

The only real excuse for getting hit is latency and that's not something "tightening" the combat would address.