I would still go swords. Riposte is OP with slower mainhands, swords/maces are more plentiful while leveling, and I would imagine sidestepping through mobs for backstabs would get old while grinding.
Still don't really agree with the OP but leveling tier lists will vary depending on what levels you and the masses are. If you no-life from the start and are ahead of most on the leveling curve then hunter/warlock is definitely fastest. If you have to deal with pvp and competition over mobs I could see some other classes catching up.