On Lunars; the primary reason I don’t want all (or even the vast majority) of the Lunars to be focused on fighting the Realm is because holy shit that means that the Realm has to be a hell of a lot more competent and powerful than it currently is. 300 (or a significant fraction of same) Celestial Exalts who make it their lives work to put you down and failing means that either a: Celestial Exalts are fucking weak or b: Dragonblooded are fucking strong.
Unless Solars are like late-game Dragonball Z more powerful than anything else, I don’t see how your circle of 5 fresh-faced Solars are supposed to meaningfully contribute to the efforts of literally hundreds of Lunars who have been working at this for centuries with no significant progress.
Also, man does that make the Realm Civil War make absolutely no sense. The disappearance of Her Redness is supposed to cause the Great Houses to withdraw troops to the Isle and leave their satrapies vulnerable because they kind of think they can get away with it. This makes no sense if there are 300 Celestial tier Exalts engaged in open war with you for the past several centuries who have been engaged in give and take conflict.