Vegeta fucks around so much. He could've killed Cell, but let him transform and even before that let him have free attacks. He, Gohan and Krillin could've tried to kill first form Freeza if he'd led the charge. I put worse than Goku. Arguably worse than Freeza because Freeza in Z had the excuse of never having experienced being challenged, so he had no reason to believe there was a real threat to his final form. Vegeta has had so many times he's gone from being desperately overmatched to having an opportunity to defeat a threat, and still took big risks just to show off or enjoy his opponent's powerlessness.
Trunks for sure tops it on non-fuckery for me. He did let Freeza attack the Earth with a large ki ball though, and let King Cold attack him with the sword. But if it was Goku he would've taken forever to kill them, if at all, and SSJ Vegeta would let Cold have some free hits I imagine.
I totally forgot how bad Gohan was against Buu. He was bad with Cell too. Kid Gohan was fairly ruthless on Namek. Future Gohan didn't fuck around but also had no power advantage, so maybe he would mess about if he comfortably surpassed the androids - or maybe the mass death of the future experience would make him as ruthless as Trunks. I wonder if that future timeline would have also mellowed the forgiveness and prioritisation of excitement of Goku and Vegeta's desire to show off, if they'd been survivors instead of or alongside Gohan.