Wanda, GF Bisquick doesn't have any shortening like the regular does. You have to add your own.
Yes, you can use butter and less salt. It's a whole 'nother thread, but sea salt is healthier than regular salt, IMO. I have never baked with kosher salt and I don't make dill pickles any more.
Plain rice flour thickens well, too. That one surprised me.