I like some more visibility in my emergent mayflies. The first picture is a good, standard pattern that is most equated with the Western PMD. One major point is what Vince Marinaro said 50 years ago is that fish indentify the curved, hanging posture of a floating nymph at the surface. He even proposed a hook heavier at the bend to suspend his patterns more vertically in and underneath the surface.
I go for this idea. Get the body of your immitation down under the meniscus while having something above providing bouyancy and visibility.
I had a pattern that I have since changed. I wish I had a picture of it, but it is so common and simple that I think you'll get the idea. I start with a slightly curved hook with an up eye. Out over the front, I tie snowshoe hare foot. I then wrap back and tie a woodduck flank tail, a reddish brown dubbed body. I add some woodduck legs spread by thread tension torque. Sometimes I dub the head with sulfur dubbing. I then consolodate the snowshoe and stand it up with thread wraps. I also wrap up the snowshoe to make something of a parachute post. Sometimes I wrap a yellow hackle around the post, sometimes not. But hte point is that this wrapping puts the nymph body better under the surface and lets the puffed-out hair tips suspend the fly. It's no big procedure, but it helps your fly orient itself well and quickly. I then color the hare post with a yellow marker. It helps with visibility and suggests a sulfur popping out.
This is a pattern type that I have become very happy with over the years. The stockies in Oil Creek get real picky, plus being stockies, don't feed as regularly as wild trout. I use this style for caddis as well. This pattern proved itself on the chalk cahill hatch in particular with a chocolate nymph body.