There are lots of good country waltzes that are very good. My favorite is "Slow Dance" by Michael Peterson. "Sandy's Song" by Dolly Parton is excellent also, but a trifle slow. "I See It Now" by Tracy Lawrence is very good also.
There are also a fair number of good country swings. I recall "Watermelon Crawl" by Tracy Byrd in particular.
Good country numbers for many ballroom dances are hard to come by, partly because country-specific dances like Texas Two Step take up much of the "musical space" that would be Foxtrot, Quickstep, etc. Also, Tango is a country dance, - just the wrong country. Good luck, hope this helps!