Voice is a skill to be developed, like any other writing skill. Give yourself permission to stretch it and challenge it and expand it and enhance it.
Today is the fifth Tuesday of the month, which means that my answer to this heartfelt letter is available exclusively to my Patreon patrons.
The question underneath your question is: "Am I allowed as a commercial writer to do the thing I want to do as an artist?"
I love semicolons; they're great. The issue is what you're doing with language and content that leads to the use of so many of them.
Books often change quite a lot as you're writing them and the book you've written may require a somewhat different protagonist than was called for in your original outline.