In a small bowl, season the warm cooked sushi rice with rice vinegar and sea salt, fluffing gently to combine.
Slice the sashimi-grade salmon into long, thin strips and butterfly the cooked shrimp by slicing down the back.
Place one nori sheet on a bamboo rolling mat with the shiny side facing down.
Spread half of the seasoned rice evenly over the bottom two-thirds of the nori sheet using damp fingers to prevent sticking.
Layer half of the salmon strips, cucumber, and avocado across the center of the rice.
Lift the edge of the mat closest to you and roll tightly over the filling, applying gentle pressure to create a firm cylinder.
Repeat the process with the second nori sheet, using the remaining rice, shrimp, and vegetables.
Use a very sharp, damp knife to slice each roll into 6 to 8 even pieces.
Serve the sushi rolls immediately with coconut aminos, pickled ginger, and wasabi paste on the side.