You pretty much summed up my thoughts as well. I only read the book once so I don't remember exactly what's different about the show. I think the Craig character is new though?
One thing I do remember is that while reading the book I didn't really like Vic all that much. I don't know if it was the way she was written or if I just couldn't relate to her in any way or what but I remember thinking it was odd that I had a hard time rooting for the main protagonist in a story. I like the character from the show much better.
I'm curious to see where they'll go with S2. If they'll do the time jump like the book or if they'll try to stretch it out for future seasons.
Overall I've enjoyed the show so far. I liken it to Mr. Mercedes where they make little changes from the source material but it seems to work well.