Photoshop: fill layer with pattern or use pattern overlay?
New mapmaker here. In making maps, there are several times when I might want to have a separate layer with a pattern filling to create various effects.
There seem to be two methods. I might create a new layer, then Edit > Fill with the desired pattern. Alternatively, I can use the desired pattern as a pattern overlay. I could be wrong about this, but with the ability to control the layer's opacity and blending modes, many similar effects could be achieved. However it may be that overlays work differently on the pixels in the layer (e.g., colored white, gray, or black) than the fill would. I also presume it is possible to only have one pattern overlay (per layer) but one can fill a layer with many patterns by Edit > Fill (should one want to).
I feel like pattern overlay gives me more flexibility. At least, I find it convenient to go into the Layer Style and preview different opacities, blending modes, or swap out patterns. Also, this seems to be the only place one can adjust the scale of the pattern. I also like the ability to try turning off the pattern by clicking on the layer style's eye icon in the layers panel, while keeping everything else about the layer intact.
I guess what I'm asking the maestros out there is: is this just 2 ways to accomplish the same thing (with a different option or two here or there) or is this a fundamental decision one should be making depending on the function the pattern will have in the overall work?