A lot would say that this is the worst path to choose because it is where you sided with the enemy and planned to go against the Church. But when I look at Fodlan, it's not a peaceful place to stay nor to live with all the small wars, conflicts, and gray morality it represents. It feels nice to be a "villain" for once and see this to the end.
While I understand this route has issues, it really shows how on point the military strength the Adrestian Empire is and how I see Edelgard in a different light now that she has Byleth on her side. And while I do see the point of having to ally with TWSITD for her war, she had no choice but to have them as a temporary ally so that later on they can be dealt with once the Church has been destroyed.
I also like how angry, confused, and sad the opposing force were when their former students/friends/classmates/relatives joined the Empire. While Gronder Field in War Time (Blood of the Eagle and Lion) feels like an emotional event of having to kill your former students for the path they have chosen, the journey from the Bridge of Myrrdin to Fhirdiad sits well for me as they see the "betrayal" as they allied themselves with a faction that started the 5-year war. The game intentionally tells the player through the cast of characters that the path you choose is wrong and wants you to feel bad about it but I personally don't care and gave them "something to believe in" with no hesitation instead. Which oddly felt...good.
I understand how "out of character" the recruited students were when facing against their former friends, but they have their reasons on why they did it. They just don't expand more and I wish they did- until I realized that they are at war. They don't have the luxury nor the time to be explaining every bits and pieces of their reasons but to fight until one of them falls to the ground.
I never felt so satisfied before ever since Star Wars Revenge of the Sith and Black Ops Cold War in Ashes to Ashes ending. I'm glad Three Houses gives you paths to choose from. As Sothis mentioned, Byleth has the power to choose a path that is their own. And whatever path they chose will lead Fodlan into a bright and new future. Crimson Flower is one of them and that path is just as satisfying as the rest but this one hits different for me and I couldn't be more happier choosing this one.