Does anyone change up the calling sounds during the setup or do you stick with the same sound for the entire time?
Depends on what call you are using. You are trying to tell a story with every call sequence you do. Sometimes it's a lost calf searching for it's mother and finding trouble. Other times it's a rabbit trying to survive the ravages of a small predator. Oftentimes, as in coyote calling, this can be the Reader's Digest condensed version of the story. For bobcats the story reads in full publication and lasts a bit longer. When bear hunting think all four volumes of "War and Peace".
The two part epilogue...probably not necessary Basically you want to gradually build up to complete anguish and desperation then finish with exhaustion and death. It's not a pleasant story you are telling so be sure to get emotional through the call.
There are generally just two characters in a calling story. The victim and the small predator. So I never like to change calls. If you start with a rodent and finish with a calf in distress the story makes no sense. So if I start with a rabbit I want to finish with that same rabbit. Start with the calf I finish with that same calf. However, if I am working the sequence with a calf or fawn call I want to start out simply lost in the woods then progress to a confrontation, a long exhausting fight and then the slow agonizing death. If rabbit or rodent I start from the confrontation and then progress on the same story line from there.
Knowing the sounds and noises is only the beginning to becoming a successful caller. All that does is give you the character voices. The way you bringing those characters to life is the difference between an average caller and a great successful caller.