Just looking through all the Black Series droid figures and Vintage Collection droids released so far, it's a bit of a head scratcher why Hasbro has not released more protocol droids. So far, the only one we have received in the Black Series 6" line is C-3PO in slightly different versions, along with a repainted Holiday version. The truly only other Protocol Droid which Hasbro has released to date in this line is Tripple Zero. One has to wonder what is holding them back since Star Wars is filled with protocol droids in no matter what movie, game or tv show you watch or play.
Looking at the 3 3/4" Vintage Collection it doesn't look much better. C-3PO (which needs a desparate upgrade), Tripple Zero and the Death Star Droid ... Let's hope Hasbro is going to course correct this and give us more protocol droids in both lines, they are great background characters for any diorama.