I've noticed in winter time where the local road crews left large piles of sand or other material, and after a snowfall, that there are sometimes coyote tracks up and all over these large, peaked mounds. I've seen it on smaller mounds, too. Your critter could be fox, cat, or coyotes, hard to say without seeing the scat or tracks.
Just seems to be a habit of all three to go up high once and awhile to get a good view of what's around them. I've read about late-winter fox sets made on top of muskrat and beaver mounds...the only prominent thing sticking up out of the snow in the relatively flat terrain of a pond covered in ice & snow.
Birds like to perch up on those things, too. Especially predatory birds. Have to be careful of sets made to nab something up on top of high points because of that.
From that high vantage point though, a set made in plain view a few steps away, one with a lot of "eye-appeal" will certainly catch a fox or coyote's eye and may work for you. Maybe a big pile of dirt next to a dirthole set, or set made with a torn-up pattern in front of it, something like that.