If you're planning on competitive PvP, its harder for the other team to call out a target when your toons are all named Clone (with a different O or E).

If you're doing more relaxed PvP, or PvE primarily, its a lot easier to trade across the team... when you know Cuddles is Slot 1, Huggles is Slot 2, etc.
On my Paladin team, Faith is Slot 1, Faith is Slot 2... making it hard to know which one to trade something to (aside from switching to Slot 2, moving away from the group, switching to slot 1 and trading to the toon who has moved...)

Some of my teams...
Might inspire you, might not...

Cuddles, Huggles, Kisses, Tickles, Snuggles
Ebola, Malaria, Cholera, Anthrax, Diphtheria
Faith, Faith, Faith, Faith, Faith