Reserving a more full review of the series for Season 2, but I wanted to drop in my thoughts on Season 1 now that I've finished it. My thoughts are basically summed up as "It's an incredible viewing experience soured by its angering ending"
Story: Pretty decent, but basic, story about political intrigue and warfare. There's a lot of blue-balling going on in terms of the story setting up a goal and the cast failing to achieve that goal, which makes sense in the context of the lore and warfare, but still plays with your heartstrings in a way that makes you feel less than optimistic about the whole ordeal. This culminates in an ending that I vehemently dislike, and ultimately the ending is lowering my rating of the whole season quite a bit as a result. I remain hopeful that Season 2 can redeem the story somehow. 3/10
Animation: High quality, if a bit stiff in places. It's no One Punch Man season 1, but at the same time it's a far cry from Dressrosa-Arc Once Piece. 7/10
Sound: Easily the best part of the show. The emotional feel of the soundtrack and the timing on it is just perfect. 10/10
Characters: If I could remove 1 character from the show, this category would get an 8 or even maybe a 9. As it is, though, there's a character who drags this rating down quite a bit because his actions and his motives are in complete contrast with one another. This isn't a matter of "Complex Character Development" or some high-brow shit - this is a matter of character suicide just to make the plot seem more spicy. 5/10
Overall: Again, I hope that Season 2 can redeem itself a bit and I'll give a more full review of the series over on that page when I finish it. For now, though, this Season is currently near the top of my bait-and-switch shit-list for having such an amazing hook and buildup for such a shitty ending.