Strange case of Dr Jekyll and Mr Hyde

So... I'll start by saying that I have very mixed feelings about this book.
Let's begin with the positives:
- a really spooky atmosphere
- Jekyll's kinda cool :)) a very interesting character with a backstory
- Hyde's kinda cool too
- this quote - ‘“If he be Mr. Hyde,” he had thought, “I shall be Mr. Seek.”'
The negatives:
- I didn't get enough of Jekyll and Hyde. Instead I got more than enough of Mr. Utterson. He's just so bland and boring, I don't know...
- VEEEERYYY slow pacing, especially in the beginning. Nothing happens until the end. And considering it's a very short book it's weird and not okay for me.
- I guessed the plot twist from the beginning. It's not like it's a bad thing. It just took away from the story a little bit. And I think that the author could have tried to make it less obvious.