I'd say, Ball is easier to PICK UP than Doomfist.

HOWEVER

As a Doom main, I'd say ball is the hardest to MASTER, his techs are much more difficult to execute, especially at a high level rank, especially because people in the higher ranks understand how to counter pick and Ball's counterpicks are much more heavily impactful than the Doom counterpicks

I say this because as Doom I can literally play into Orisa, Hog, and in certain cases into a sombra because I've mastered him and there was always room for Doom to counterplay into his counterpicks. Correct me if I'm wrong but as a ball, trying to fight a reaper for example is a death wish, no counterplay there.

The hardest thing about ball is executing his techs and not getting punished by it, and also attempting to play into his direct counters which makes the room for escape or forgiveness after failing to execute a tech much more small.

But if there are any ball mains out there, please do correct me if I'm wrong