actually the echo buffs makes some fights far harder than they originally were.

Leviathan extreme is near impossible with a fully geared group and 25%

Twintania is much the same. You end up with all kinds of mixed up phases.

Moogle Mog Extreme is far harder with the echo, it is so much easier to make mistakes and push a lesser moogle too far by accident.

Because of the phase based nature of bosses, the echo is actually a detriment.