It's come to the point where the only optimal movesets for Dragonite do not contain Dragon Breath, and only Dragon Tail. The reason is because specialists have got much stronger (previously, you could use Dragonite against fire pokemon or water pokemon and still come out on top of their respective counters despite not dealing SE damage). Kyogre vs Fire pokemon makes dragonite look like a complete joke while in the past Dragonite (DT/OR) made Vaporeon look like a joke. Only DT/OR can minimise the gap between Dragonite and the optimal counters and keeps Dragonite's place as a generalist.
Dragon Tail+Hurricane still works as a machamp anchor but Lugia does it better and Rayquaza is imminent now.
Dragon Breath+Hurricane on the other hand does too little damage (Hurricane is not a very good 1 bar move and Dragon Breath is not an exceptional fast move either)
I would keep Dragon Breath and Outrage. It's the only option that keeps DPS competitive while keeping the legacy Dragon Breath.