One "magic trick" I've used for salmon is to sprinkle a pinch of brown sugar on top, in addition to salt and pepper.
I haven't made any on my Traeger yet, but my go-to on the Weber kettle was to use Oro King salmon, cedar plank, and just the seasonings mentioned above. Skin-side down on the plank, no need to flip during cooking, take off promptly when the salmon reaches 125 degrees internal. When prepping the fish, cut thinner sections away from thicker sections so you can cook and monitor internal temperature separately as the thinner ones will obviously cook much faster. IMO the thinnner ones are the "chef's secret" best-tasting bits as long as they aren't overcooked.