I also tried the elimination diet for my son after finding out that he was allergic to certain foods. In addition, he had severe excema. His behavior improved radically after eliminating all corn and corn derived products (almost as hard to do as removing gluten). We also started giving him fish oil which has curbed his excema issues. He still has dry skin, but he is no longer scratching/crying until he bleeds. I understand that fish oil is also beneficial for behaviorial issues.
Regarding vaccines, I had read quite a bit while pregnant with my third how harmful vaccines are, especially at such a young age, so I choose not to have her vaccinated until she is 2 and then will do them separately.