Derek: Well, you asked for it
A - You need a control loop here. Control loops go on both sides of the edge, not just one
B - This loop has no purpose
C - This control loop is getting tighter towards the top. It needs to keep a consistent distance away from the corner to give a clean result. Also, both control loops are to keep the same distance, to create a clean curve. Currently C is very tight and D is wide.
D - Same as C. Gets tighter towards the top.
E - Double control loop. Again you just need one. You only ever need maximum one control loop on each side of the shape you control. When you want a melted look on purpose, you can use only one, or none, but you never need more than two. The isoline view can be misguiding. Study the actual geometry created, not the isolines, to learn how subdivision really works.
Since I see a lot of people make this mistake, I put together an illustration:
A: 3 quads next to each other, the last one taking a steep plunge. So you'd think that would cause the entire mesh to curve, right? Wrong, any one polygon can only ever affect its immediate neighbours when subdivided. The first quad shape is in fact still the exact same shape and position it was before subdivision.
B: The first quad is still fully intact. We don't need any control loops to protect it from the curvature created by the third quad.
C: Adding control loops to get a sharp corner. Both loops are at the same distance from the edge.
D: The isoline makes it look like the curve is uneven because the one control loop is pulled down so much, but if you look at the silhouette you see that's not the case. The corner curvature is perfectly even and highlights on it will look clean.