Lots of good stuff, as usual. I like to keep it simple when I have great quality fish, and the only rule that can't be broken is not to overcook it.

Once in a while, I do like to mix it up a bit, but I always try to avoid overpowering the natural flavor of the fish. Here's one I really enjoy on occasion:

Salmon fillet, skin-on and sliced into desired portion sizes
Light olive oil
Salt
Pepper
Fresh bitter greens (spinach in a pinch)
Sherry vinegar
Garlic, chopped
Shallots, chopped

Season fish with salt and pepper. Coat with light olive oil (you can use extra virgin, but it will burn at high heat and lose most of its aroma, so why waste the good stuff?). Grill on high heat (gas for milder species, charcoal for sockeye) until fish is medium-rare to medium. Pull off and let rest.

Heat a sauté pan until smoking hot. Add a small amount of olive oil to the pan, immediately followed by garlic and shallots. Toss a couple times, and quickly add the greens, followed immediately by the sherry vinegar. Sauté for about 30 seconds, or until all greens are wilted.

Place bed of wilted greens on plate. Remove skin and lateral line from fish and place atop greens. Garnish with toasted sesame seeds. Eat.