You may leave out salt and sugar altogether for hot smoked salmon. Simply season according to whim and smoke at your highest temperature setting. The fish is done when it flakes, or firm to the touch.
A simple compound butter can be made with lemon zest, a few drops of juice and some chopped dill. Combine all, roll it into a tube shape with plastic wrap, chill, slice and place over the hot, finished salmon. The butter can be kept frozen for several weeks.