How much worse do you think ephemeral anchors are (incentive wise) than the current dust-anchors? At first glance I would think the 546 sat difference is insignificant in a >200 sat/vbyte environment.
Meanwhile 0-value outputs reduce complexity and afaik are essential for ln-symmetry.
One final point: regarding recommendation 3, I don't think anyone would want to move forward with v3 without ephemeral anchors.