Thank you for the reply, I agree with you 100%

I think it's at the end of chapter 4, Sigurd has that moment where he says something to the degree of "Dammit! I let Eldigan die fighting a pointless war!" He had been in Agustria "governing" the country for months while the Grannvale governors were clearly exploiting the people. If you visit the villages in chapter 4, some of them say stuff to you about how they wish Grannvale would just get the hell out of their country.

I always find it absurd on FE forums when they have discussions about Eldigan and a ton of posters talk about how he is the quote on quote "stupidest character in the game". Actually, he's the smartest character between Sigurd, himself and Quan. Eldigan is the only one that can see the imperialistic drive behind Grannvale's wars and that they are literally sending this overpowered unit and his small band of friends to your country to completely topple it. (Sigurd is pretty much Fire Emblem Jesus as a unit and can solo most of the first generation, but that's a different discussion)

The problem with the second half of Holy War is that it's just not as interesting or as fun as the first half. It follows the same formula of most Fire Emblem games, where some young prince hiding in isolation rises up to fight an evil empire and routes them chapter after chapter with no real trials and pushback. The stakes are only raised higher cause Grannvale is more properly fleshed out than the empires of the other games.