Have you been to all of the various attractions near Rapid City besides Crazy Horse and the National Parks/Monuments?
There are several attractions, so it's hard to see all in a short visit, but I remember fondly my visit to Reptile Gardens (the largest reptile zoo in the world) during my first Black Hills trip when I was 7 (which was actually the only time I've been to Mt. Rushmore). My favorite place I've been to in the Black Hills region is probably Custer State Park, which is a beautiful place full of good wildlife viewing; but also a very horribly named park, and the town of Custer is full of unsavory characters, many of whom are racist hicks.
The Black Hills/Badlands region is beautiful and I want to see more of it (including Mammoth Site in Hot Springs), but I find the West River culture a bit off-putting. West River people are generally less pleasant and welcoming than East River people, from my experience. Even the West River I meet in Sioux Falls are usually not people I get along with much, and they complain about "liberal, snooty, uptight, big city" Sioux Falls.
When I mentioned that my family and I were from California, the people from Sioux Falls seemed interested, but guarded. Almost like we were tigers in a zoo that might not be been in an escape-proof enclosure. I can definitely see what you mean. West River did seem a bit aloof; might be from having to deal with more tourists than Sioux Falls.
I definitely saw signs for Custer State Park, but didn’t go there. My family and I were amazed at all of the attractions that there would have been if it wasn’t the end of April when we went. We did drive by the Reptile Gardens and a rhubarb wine place (didn’t know you could make wine out of that!).
Deadwood was a bit better than I was expecting, but it still felt like a performance compared to some of the old gold rush towns in California. Granted we just drove down the historic main street without stopping.