How to monetize a Spotify app?

A year ago, I launched a side project I had been keeping to myself: https://brew.fm. I posted on Reddit to ask for feedback, implemented the feedback and showed reddit the result. I also posted it on hacker news where it became the top story for a short time. These 4 posts let to 4000 users.

I had been paying $50 a month due to the NoSQL database that didn't clean up after itself. Last week I rebuilt the site so costs are down to $80 a year again, which is just the .fm domain. I simplified the product and kept only what was used frequently.

I've been using the site at least weekly myself, and there's a handful of regular users. I haven't sent (transactional) emails and the platform is abandoned by most users. The last 30 days 77 visitors used the site.

I'm now curious to figure out if this project can be monetized. Worst case I learned a few things while trying. My problem: I have limited and outdated experience in this field. I'd love to hear what others would do, or get feedback on my approach.

My plan:

Charge a life-time fee, eg $30. Only search for max 50 artists involved in a playlist for free. To see releases of all artists, pay the fee. Use ads like Instagram ads to create a steady stream of new leads, and fingers crossed that the costs are lower than the revenue. Try to get on something like AppSumo.

If that doesn't work, leave the product free. Aim for the masses. Get Tiktokkers to do demos of the product. Charge for ads in a weekly personalized newsletter with new releases from user's top artists.

If you have a minute, I'd love to hear your thoughts!