Although I don't watch as much anime these days, I do keep an ear out for the music occasionally and it's not been a vintage year in terms of OPs and EDs for me (there's been some excellent animation, though, which makes up for it.
I've only bought the following:
Yuri on Ice - History Maker (OP)
I still think the Eurobeat is a bit of a mistake, but I love the xylophone and the strings in the chorus; I also think it's very effective at capturing the tone of the show; it feels like it's got some of the grandeur that the ice skating routines evoke (the show's OST is outstanding in its variety, incidentally, even if some of it is a bit naff).
Battery - Ashita, Haru ga Kitara (ED)
It's saying something that this is just a pop cover that sounds almost identical to its original version, but it's a classic - it's like the female version of Mr Children's Tomorrow Never Knows.
Amanchu! - Million Clouds (OP)
I'm a long time Maaya fan; I'm grateful and perhaps a bit surprised she's still doing anime themes. This isn't one of my favourites but at least she's still putting out tracks that don't sound like every other anison on the market. I also really like the lyrics - they're quite sweet and poetic.
Kabaneri of the Iron Fortress - ninelie (ED)
I know, I know, we're all contractually obliged to hate Sawano. I don't (well, sometimes - I'm not always a fan of his scores, and a lot of what he writes for male voices is boring Nickelback-esque rock). I love his overly melodramatic pop barnstormers, even if they're lyrical nonsense, and ninelie is just
brilliant - the man can certainly write a chorus. This is probably my favourite anison of the year...
The Asterisk War - Ai no Uta -words of love- (ED2)
I thought I was going to love this after I heard the TV size version of it - I really, really like Rasmus Faber's work in general, and Waiting For The Rain was a
gorgeous ED for the first season. I kind-of feel the chorus is a bit underwhelming here and the song doesn't really increase in complexity in the way I hope it will each time I listen to it.
Outside of anime, there was a decent game OP from
kokia, and I will admit to being rather fond of
World of Final Fantasy's OP, but I've not really heard much that's caught my interest.