ive read a lot of his stuff, he is one of my favorite authors. Could never get into the Alvin Maker series. The Ender series isn't all that great after the first book and the "parallel novel" that came out way later.
I really enjoyed his "Homecomming Saga" 5-book series. I never see anyone else talk about that one. It seems he is mostly known for his ender work. Card has some good stand-alone novels like Songmaster and The Worthing Chronicle (my personal fav).
ive never found the mormon stuff to hurt his writing. everyone draws inspiration form somewhere.