Let's go with something a bit more agreeable than usual.
Sting Ray should return in Splatoon 4, reworked to have much better handling at the cost of its global range and damaging shockwaves. The concept of a special that trades its user's main weapon for a massive, wall-piercing laser is incredibly fun, but Nintendo pretty much immediately fumbled the bag with the special in Splatoon 2 by giving it a giant AoE while being fired consistently. Add onto that the fact that they never limited its range, and it's no wonder it ended up being so hated. With those two aspects removed, the special could finally enter a spot where it would be loved for its high skill expression and supportive nature.