Can something be done about alliance raids?

[Seraphor]

For point 2, they've tied Void Ark into Tataru's questline so they're already implementing this more carrot approach to encourage participation in this optional content.

For point 3, I'm not sure increased rewards are going to fix the issues with Nier. Because they have such damage sponge bosses, you know you're in for 40 minutes minimum even with a high dps raid that knows mechanics. It's hard to make that ever palatable when even if someone isn't fishing for CT they can bail and get VA or Ivalice and still spend a lot less time with a lot less irritation.

Well my point 3 was fairly simple, even if my idea for it was more specific.
Incentivise running those later raids. If that incentive comes in the form of reducing the amount of HP the bosses in those raids have, then by all means.