In our line, every single location we set could take either coon or coyote. If we only want coon, we use DPs, 160s, or cages. Otherwise every coyote set we make could see either species taken.
In several of our locations we hit the coon trails hard with DPs and 160s, then made traditional coyote sets at pinch points, travel routes, edges, and focal points in open areas. We catch about as many coon as we do coyotes in those "coyote" sets and we always get coon in the coon sets/locations.
This year we had fairly mild weather for almost first 1/f of December so we also ran a lot of water sets like pocket sets and baited bank edge sets. That allowed us to take a lot more coon from those locations than we normally could that time of year, and though I can't prove it seemed to help keep coon out of our coyote sets out in nearby field areas at same locations.
In short, I would never hesitate to set for both coon and coyote in same locations. We've had multiple catches of both species in same locations by doing this. Set for each, set on sign, and one doesn't seem to really bother the other in terms of visits. That is completely natural thing in our area. We have had many checks where one coyote set had a coon and other coyote set had a coyote, both in plain view of each other. Same with a coon in a cage or DP and a coyote bouncing around at a nearby set. Our area is a mix of ag land, creeks, lots of features attractive to both species.
Jim