If you've got ~$10 to spare, I recommend picking up Alex Wrekk's zines on beginner witchcraft (available at portlandbuttonworks.com and probably on Etsy). As zines, they're a very fast read, but they pack a great punch. Wrekk talks a lot about (and gives some practical tips for) making your witchcraft your own, something that works for you, right down to whatever you put in your BoS or on your altar, if you even need one.
I always thought that keeping an "official" BoS wasn't really for me, partly because the BoSes I'd seen on blogs and social media were extremely artsy and seemed to essentially replicate the content of any "intro to Wicca" book. (Standard warnings about social media not reflecting reality go here. :))
But I've got one. I write notes/quotes from helpful books and zines, the meditation sessions I attend at a local temple, tarot spreads I particularly like, ritual stuff that I want to remember, sigils, and witchy sources if they really help me. If it's something I want to remember and it's related to my spiritual life and practice, it goes in there. It's also cool to flip back to the beginning and see how I've changed and grown.
So, writing poems? Song lyrics? Reflections on Norse folklore and practices? Doodles of dragons? Why not put it in your book... it's yours, after all.
Also, I think having a single, centralized, physical BoS isn't for everyone: some of us keep a lot of content on social media, Tumblr blogs, Google Docs, or wherever works for us. Also, there are a LOT of 2022 witchcraft and tarot yearly planners going on the market right now; some of those might be a good place to start, too.
As for Norse stuff/heathenry, Ocean Keltoi and his group might appeal to you, especially because he talks very plainly about some of the issues in the community.