I haven't published a whole ass book, buuuuut given the description above, I would self-publish for a few reasons:
1) It is more immediate, which is great in terms of feedback + development.
2) Your book sounds somewhat niche, which is great, but might be harder to sell.
3) You'll probably learn about the sales/promo side of things (most writers hate this, but TBH it's how you have any sort of career).
4) Agents are a relationship like anything else, and it may take time to find someone who is a good fit.
5) It's not a forever commitment. You can always get an agent later if the mood strikes you.
You can 100% have a satisfying career self-publishing. Just don't break the bank. You should peruse Agents and Books on Substack, she has a lot of great insights into the industry!