Looks like no one is gonig to say anything until I make another response.
Here another example of excessiveness in 40k, let take a look at the Eldar Fire Dragons, each one of them has a melta gun for 16 points each. Also when you compare Retributors to your other heavy support choices are you going to take them? I mean how many times do we see sister army list with 3 or 2 Excorists and no retributors? You have to give them something to make them attractive choice.