I've been there. Hell, I feel this way every so often and I've been writing for years. Here's something that helped me when I first started.

You know your favorite book? The one who's style and prose you strive to emulate? Read all of the negative reviews about it.

You know that book you hated? Who's prose and style and content were everything you want to avoid? Read positive reviews about it.

Writing style is so subjective: there really is no good or bad. For all of the readers who love purple prose and poetry, there are an equal amount who love concise and easy to read prose.

That being said, the best thing you can do for yourself is read, read, read, and write, write, write. If you want to improve, try doing a writing challenge, and force yourself out of your comfort zone. Find your favorite quotes from an author and write around them (as an exercise; obviously don't claim another's work as your own).

My favorite exercise for finding my style balance (former purple proser here) was writing down a simple paragraph, or take one from an old WIP. Then I would dry it up and get as simple as possible with it, then go the other way, and add as much metaphor and simile and lurid, dripping prose as I could.

Lastly: your work feels predicable to you because you wrote it, and you know what happens. It's not bad to want more readers; have you considered taking requests from people in your fandom? A community is a great way to get feedback and figure out how to balance what you want/like to write, and what people are reading.