Ending sequencesa re kind of artistic showpieces, but when you get down to it it's 1-2 minutes of special animation for PR purposes. Most of Frieren is about whimsical character moments over very generic backgrounds (also true of the manga); people love it for the bittersweet characters and trope-skewing gags. I love the show but it's not the best example of technique or visual innovation.

Mappa is imho the current heavyweight studio, doing everything from spectacular action setpieces with bold visual experimentation in mainstream stories like Jujutsu Kaitsen to the extremely labor-intensive stylization of Dorohedoro.