Just my opinions but getting rid of enrages would just cause more problems. If there's no threat of failure when you don't have enough damage to kill things in a timely manner that's when things like t2 enrage strat crop up. There's always a way to get around things and locking party comp would just be annoying, for a moment imagine you don't have enough heals to do a certain mechanic or your dps is taking forever so the healers are running out of mp. Now bring in 4 THM with cross classed Stone skin and physic, problem solved, since you have 0 worry about killing it in a certain amount of time just have them all using stone skin on the tanks while in umbral and rotate, instant cheese.