This is unpopular opinion but GD is my least favourite route - maybe Church as well, but I haven't played it yet. Claude is nowhere as emotionally invested in the war as Edelgard and Dimitri, and it is difficult to resonate with his ideals when we don't have much background on the land he keeps talking about. In the final chapters if you walk around the castle the NPCs literally say something like "Wait, is there still more? When is it going to end?" 🙁I think it's a bit of a wasted potential because GD is the most down-to-earth house, so I had hoped that it would focus more on the sufferings of the common folks for the "faith, hope and dreams" of the nobles, but it didn't unfortunately.
So far my favourite is BL, mainly because I find Dimitri a more interesting character than Edelgard.