I use Discord now since most of my friends are on it, but I've always been a fan of Mumble (and murmur server) since it's high quality software and open source.
I also made https://guildbit.com years ago for gamers that want to just quickly spin up a temporary server with their friends. I still operate it today since there's still a few users out there.
I think it would be cool if someone were to create an open source Discord clone using Mumble/murmur.