He breezed through most of his opposition at ww and sww so if he does make a comeback, it would be either too little (any ww out there or a Canelo rematch) or too much (GGG).

On the other hand though, Pacquiao couldn't be worse than Berto and he did fight Berto after all.

Personally, I'd prefer Golovkin. Realistically, even, because it would be one of his very few hard/defining fights, so that would justify it from a fan's point of view —which he probably doesn't give a sod about.