Personally, I think you're overthinking all of it. How far did you travel to get to the areas you were hunting? I take it you don't live in Utah. Right there is a problem. You are hunting land you know absolutely nothing about. It's hard enough to raise a coyote in an area you're familiar with, let alone trying to figure them out in new country.
I only use mouth calls, mainly because I don't haul around extra equipment.
When I get to my first stand, I call for no more than a minute. I start out low and slow. Then the wait begins. More than what gun you use, what call you use, whether you wear camo, patience is the most important. I try to use high ground and try to sit in front of a rock or brush to break up my outline. Wait, maybe at least 10 min. You might get lucky. You might get one in close. You also might get one curious at the furthest range of your call, so give it time to cover the ground. I've watched them cover great distances on the way to the call. If you see them coming, stay off the call. You can only screw things up.
If I were you, I'd stick close to home so I could really learn the area I am hunting. Hone my calling skills and learn to have an abundance of patience. Call and scan. Sometimes they will come at you like a freight train, sometimes they will be cautious and take forever. Basically, it's on the job training.
