I really loved the music in KokoSake too and I'm definitely getting the soundtrack after this. I also liked the music by Radwimps in Kimi no Na Wa, though maybe that's just because I heard that main song on every single radio in Japan last summer lol. Hearing the Chihayafuru ad also turned me on to Perfume, though I'm not usually an idol fan.
I'm also weeb trash so I listen to a lot of OP/EDs and artists I found through their work in anime. I used to listen to a lot of Wakeshima Kanon, LM.C, Girugamesh (I know), and vocaloid/nico nico vocaloid covers, but I haven't had much time to find good new stuff lately.