If I'm reading this right, you are talking about putting a carcass out on the ice of a frozen lake/pond, drawing dogs out into the open, then getting down to business?

I wish I had the problem of deciding how to call coyotes on ice, doesn't often get that thick down here for enough of the season for me to have done it.

Do the dogs travel on the ice in that area? I've seen a lot of track across rivers, or out on the edges of ponds to get to the waterline, but I know other parts of the country that get feet of ice might have game travel regularly over ice.

I like the "cove" idea, for the fact that I don't ever expect coyotes to travel very far out into the open. A cove might provide a bit more confidence than a more open patch of the ice.

Use your bait location to establish a "kill box". If you want to shoot them off of the bait, then that's your kill box. In that case, I'd want to be closer than 150yrds from the bait if I were shooting a hornet (or most other rounds). If you place your bait so the coyotes have to pass by your shooting position, then I'd still want to be close enough that if they come in from a surprise angle, you can still make the shot (i.e. not over 150yrds).

Calling over bait always draws mixed advice. I've had good results either way, between sitting in the truck playing cards with my brother-in-law watching over a bait pile as well as when calling with distress calls over the bait. Not saying that predators hunt using logic, but I tend to believe that good sounds can travel far enough to attract a coyotes ears to bring their nose close enough to smell bait. Good smells will only attract noses that smell them, meaning close enough to catch a pool, or in the right location to catch your good smell on the drifting wind. Crows and eagles will be good confidence builders, but good sights only attract eyes that see them. Again, the sound may lure them to see the scavengers on the bait, tripping another competitive predatory trigger.

As far as shooting the first one that comes in vs. waiting for more to show, a bird in the hand is worth two in the bush. Nothing says you can't wait a few minutes to see if something comes in, and then shoot a coyote as he's walking away from a pile if nobody else shows, but given a high-percentage shot, I generally take it. If I see one dog coming in with others hanging up out of range, then I'd wait for that one to get cozy and build their confidence, but if they aren't in sight, I take what comes. Connecting on doubles is rare enough as it is, especially if your first shot is 150yrds.