Brioche is new to me but I can say it is fun. How complicated it is to you is going to be a personal thing. For example, I can't really do lace because I cannot memorize the patterns so lace is very, very complicated for me.
This brioche is challenging, but in a good way. And once you truly learn it, that's it. You'll be able to do it moving forward unlike say, lace, where you'd still need to memorize each new pattern for every new project.
I do think Soundwaves is a good first brioche knit project. It's written very clearly and the project itself is direct and pretty simple in what he's having you make. It looks more complex than it is. Plus, it's good practice. And Stephen has good brioche tuts. That all said, I'm going to be moving on to Bixbite before being anywhere near finished Soundwaves because that was my goal from the start. Though now I'm a little nervous because I found an error in my Soundwaves this morning and was really at a loss on how it happened and how to fix it/move on. That is, I did move on but I wound up doing a decrease in order to do so. Don't let me scare you. This all sounds worse than it was.
Many pets for the wee kid