They're all pretty dangerous. I think if Haye is anywhere as good as he was against Chisora in 2012, he should clearly be the best of the lot. Joshua's hard hands are irrelevant when he can't connect. Prime Wlad couldn't lay a glove on Haye so I doubt Joshua can, provided Haye hasn't slowed down considerably in the meantime. Quite a big "if" at the age of 35 though. The two bum fights he had were meaningless.
Ortiz would destroy Joshua. Have? Who wants to see Haye prance around the ring for 12 rounds throwing 8 punches a round? Not me.