My rating system is simple.

⭐️ ⭐️⭐️⭐️⭐️ ~ I loved it. The story and characters were exceptional and I would read it again. Highly recommend you read it.

⭐️⭐️⭐️⭐️ ~ I thoroughly enjoyed it. The story and characters were gripping and kept my attention and focus. I recommend you read it but I don’t feel a desire to read it again personally.

⭐️⭐️⭐️ ~ It was good. It wasn’t exceptional & there were things that I didn’t necessarily like about it but the writing and story were good.

That’s it.
I prefer not to rate below a three star because I know how much effort and time is put into writing a book/novel.
If I read it but didn’t rate it I don’t list it.