Personally I think Libra needs a more generic vulnerability replacement effect so that we can shave 2 buttons and actually have some room for utility actions on DPS. Being able to hybridize is also one of the few aspects of the job I liked pre-70. The other problems with the job mostly stem from lacking spots on the tank and healer side of things. I think a minor defensive cooldown that could be used on allies and get a boost based on your role would add a lot. Adding some kind of MP management tool other than Blood Drain would also be helpful on tanks in particular. I'd also prefer it if we got instant-cast melee-only single target filler as alternatives to the current caster suite to round it out a bit. It doesn't need much more than that unless they're gonna do something to replace Moon Flute.