Feedback and Making Changes

So. My debut novel The Unknown Neighbor has been out for over a month now, and I've gotten some feedback on it which seems fairly decent to me. As I write this on Sunday morning, I have:

Five 5-star reviews/ratings.  4 on Amazon.com and 1 on Goodreads.com
Three 4-star reviews/ratings. 2 on Amazon.com and 1 on Amazon.co.uk
No 3-star reviews/ratings.
One 2-star reviews/ratings. On Amazon.com
Three 1-star reviews/ratings. All on Amazon.com

Not a bad spread. It actually tells me something good. Pe...