Back in d1 it was good because you got twice the weekly loot. This went away in d2 though. If you have 2 hunters, you are only gonna get rewards for each activity once.
2 of the same were great when getting ready for a raid. You could share gear, etc. Now you are rewarded bass on vault and all characters, not individual character power. So unless there is something class specific you are chasing, there is little need for 2 of the same. Unless you are attached to the character or what a male and female of the same class. But hey, it’s up to you.