The Yikes of Season 1 aside, BBK/BRNK is pretty good.
I enjoy how much the art style develops -- the first season has some particularly janky "Cell-shaded video game cutscene" level animation, but the later seasons really start owning the fact that this is 3D and you gotta do certain things in a 3D way to get 3D to work. Characters don't have the kind of dynamic, expressive lighting something like ASW games have, though, so it's still not the best cell-shaded CGI I've seen.
The fighting coreography is wholly competent and extremely gorgeous. Posing is good and fight scenes stay readable thanks to a solid use of colour and character designs that have strategically glowing elements, letting the eye orient itself even when shit's going crazy.
Also, the weapons have a very particular heft to them, especially Raijoudou and Kinoa's larger sword -- an interesting example because it can literally float in the air, yet moving it while it's floating has a delay that sells the mass and power behind the swing really well.
Oubu's design isn't super special but the rest of the Buranki are pretty cool-looking.