Bill Tindall, E.Tn.
I built an easel for spraying anything I can mount on it because I prefer spraying surfaces that are perpendicular, more or less, to the ground. It becomes easy to have the spray pattern perpendicular the target in this orientation and I can see the coating being applied better. Seeing the coating hit the target goes a long way in preventing runs.
Anything drifting down for above is less apt to settle on the surface. Things too big to set on the easel will be sprayed flat.