The Weakness of GMS Luminous

That's being unreasonable. But in the first place the cooldowns are long enough for you to charge up one point to pull off an Equilibrium Echo. If one point in, say, Light, is all you need, then it hardly makes a difference if you lose all 10 points, or just one point.

Death is unavoidable at times, true, but then that simply becomes part of the game.

Hadriel

Agreed, in most normal cases you will be fine. Hard hilla dispels, seduces, and cages you so much that you really don't have time to charge up another gauge fast enough though. I would believe I've done enough end game content to know that the same strategy doesn't work everywhere, same for teleport as an avoiding skill.