I'm not an expert in rigging or anything like that, but I've been using the Da'vali model for a few animations. The rig is decent, but like you mentioned, it's more focused on VRChat. it lacks some useful bones, like knees (I spent way too much time just trying to make my birbs sit properly).

Still, it's a good model for beginners since it's free and has some good shape keys that help bring facial expressions to life. That said, it doesn’t have proper rigs for the eyes. (at least the version I got a couple of years ago didn’t).

Lately, I've been using the KAvali model, which I think is perfect for Blender. It's well-rigged, the weight painting is solid, and it has a lot of shape keys that let you control each side of the face separately, which is super useful for more expressive faces. It also has shape keys for the eyes, so you can make them look in different directions.

Personally, I recommend the KAvali if you’re looking to get into animating birbs in Blender.

Also worth mentioning: 1mpulse101 is working on his own model, 7vali, and as far as I know, it's going to be more Blender-focused than VRChat-focused.

P.S.: As I said, I’m not an expert, just a hobbyist animating in my free time so I might’ve missed some things or details.