Everything you said is right except for the part about the sheriff.
I guess he's a good character. He just rubs me the wrong way. He's so noble and mostly virtuous by the book, but he just comes off extremely boring and not enjoyable. He's basically the opposite of Al.
There are more than enough great and enjoyable characters to go around though. I didn't even mention the Doc, Charlie Utter, Miss Isringhausen, Tom Utter, Dan in some ways, Jane and of course Wild Bill, who we only got to see in full bloom a couple of times.
It just now occurred to me that, including and maybe because of Cy Tolliver, there is really no interesting characters (other than Wolcott), centered around the Bella Union. They are nearly all boring or just plain contemptible.
