You are right.
Her first return, October 2012 - November 2013 was the two failed weddings with Brady.
Her second return, July 2014 - November 2014 was when she kidnapped Daniel, got John out of his coma, had a run-in with Susan, almost slept with Daniel, and left Salem with Theresa's embryo.
Her third return was in April 2015 when she held Theresa, Brady and Melanie captive in the castle in Italy, before she was pushed out of the window by Marlena.
All of her returns were written by Tomlin and Whitesell. I think, and hope, that Ron will write Kristen better than they did.