Claude's "I just want to see what the world is like without you, Rhea" is probably the most retarded line in the game and isn't the world without Rhea just Almyra? A land where his people are thrown against the meat grinder and the rulers are either too ignorant or arrogant to change?
Not to mention without Rhea and killing Byleth on GW, the Agarthans have absolute free reign over Fodlan which is the absolute worst outcome.