You could read Let's Talk About Love: A Journey to the End of Taste by Carl Wilson. It's an essay(ish) book about taste in music, funny to read and not too long (~200pg I'd say).
About the comfort zone, you could try and read something about contemporary problems and predicaments. A poison like no other talks about plastics in our everyday life (not fun), or something really old like Seneca's On the Shortness of Life: Life Is Long if You Know How to Use It (~100pg)
https://bookwyrm.social/ is what I've been using. I'm not an avid tracker though.
I tried thestorygraph, liked the idea but I don't like my readings to be guided by an algorithm and also I don't feel like paying for a platform, especially if I'm not using the main feature (the recommendations)