The menu looks great to me, but in Texas we would always add some brisket. Some may not want chicken that has been fried. I like two meat choices. Another could be ham.
If she is putting the cakes on the tables for a centerpiece (and how lucky to have someone do that), you could add those little hay bales with various colored western handkerchiefs laying across the haybale and then putting the lovely cakes on that for height. You could add a few horseshoes leaning against the hay bales and some of those stars sticking into the hay (Hobby Lobby). Okay, the stars might be just a Texas deal.
You could also incorporate the handkerchiefs into some bread baskets. I think the western handkerchiefs and red and white gingham table cloths are awesome together.
Each place setting could have a handkerchief and silverware in the mason jar. When they take that out, they can use it for the tea, lemonade or water. I'd have servers going around the tables and filling the glasses.
Or you could use handkerchiefs to wrap the silverware and tie up with jute.
Boots filled with sunflowers and Gerbera daisies for centerpieces, put a few lanterns around.
My country is western to me. lol
That is all I have on the top of my head. I'll add more if I think of anything else.