As for the Silver Efex Pro b&w layer... that is they way to go! Unfortunately not a lot of our CiC brethren does have this with them so I did not introduce it to the equation. That, my dear friend is to your advantage.
If you use the "high-structure" preset on SEP that you have that will give you far satisfactory results as you have validated it. Pretty neat, huh.
Remember, if any of your adjustments looks too much on the end result, you can always lower down the opacity of the blended layer to bring down its effect. That's the power of layers and photoshop! Way to go, Rob!