Those powerful slow moves can at least be used if you get a shield break. Although reversed Warlock Punch is stronger, if you want to show them Ganon's nutz before axe kicking them, you have the option to go for it!

Same with Dedede's Jet Hammer. Both are horrible moves nonetheless, purely there for disrespect, but at least there's that.
Palutena's f-tilt may be slow, but it can punish and hit spot-dodges at least.
>Falco Lasers on the list.
You can add damage after knocking opponents away and eat double jumps with them. They are a shell of their former glory, but these are far from being terrible.
An interesting thing with Little Mac's haymaker is you can use the super armour frames to land safely and eat through attacks. Overall not worth using over Little Mac's other landing options, but there's that.
Imo, Sing is the worst move in the game. It lasts too long and is so easy to escape the sleep status. You can wake up before Jigglypuff finishes the move and punish her for putting you to sleep, unless your % is too high for that to even matter when Jiggs could just use another move to KO you.
Doesn't even work on opponents who are in the air and know how to jump or stay away from the ledge when you're jumping and re-grabbing the ledge (you have a million better options as Jiggs in this situation).