I have now received a reply from BBC Prime, and their responses to my complaint seemed quite reasonable.
They are obviously aware how dissatisfied people are with the high level of repeats, and they assure me that they're taking steps to eradicate this with a new programming format to be rolled out next year. The new schedule will feature different series to those currently being shown, and they have asked me for suggestions as to what type of programming I would personally like to see.
The proof of the pudding however, is in the eating, so I await with interest developments next year.