Having a good community also helps to separate the good books from others. I mostly read fantasy and the community on reddit is so good to get recommendations, participate in polls, interact with authors, etc. There's also a yearly contest where 300 self published books are reviewed by bloggers. Here's a recent poll [1] and here's a somewhat older thread for recommendations [2]

I got a Kindle Unlimited subscription this year and some of my favorite series are:

* Cradle by Will Wight

* Arcane Ascension by Andrew Rowe

* Heartstrikers by Rachel Aaron

* Worm by Wildbow (I'm counting webserials as self published too)

* The Sword of Kaigen by M.L. Wang

[1] https://www.reddit.com/r/Fantasy/comments/cwz83u/the_rfantas...

[2] https://www.reddit.com/r/Fantasy/comments/7lib3d/what_are_so...