Is the salmon portions individually packaged? If so, they will thaw easily by being left in the package and dropped in a small container of cool water. If they are not in a sealed package, then do so by dropping in a small zip-lock freezer bag, squeeze out the air. Change the water every portion, and the bag.
Salmon tissue breaks down if thawed fast. If your salmon is individually packaged you can put your pieces on a tray of ice in refrigerator, they thaw more slowly, and are only more apt to be partially thawed so will have a longer storage time, but only require a very few minutes out on the counter. Just strip the packaging and blot dry with a paper towel and give them a moment.
Soften some butter mix with one part oil and a 1-2 drops of liquid smoke. Use this mix on the fish, season and grill.
Try some seasoned, compound butters. They keep well, you can write them up differently on the menu, offering more selection. They also melt over the fish and add moisture. Shape them into a triangle shaped log, when sliced they look sharp on the fish.
Lemon zest, dill weed, shallot, onion powder, salt, teaspoon of white wine.
Dried cranberries, blueberries, lemon thyme leaves, garlic powder, lemon zest, toasted nuts, teaspoon of white wine
Crystallized ginger, dried mango/papaya, orange zest, cilantro, orange juice or wine.
The little wine or liquid is required for all of the flavors to "bloom" or balance out in the butters.