While Craig is busy writing In Her Majesty's Name, I've been giving the ITEN retinue lists a going over. As well as releasing a new Necron retinue list, I have also prepared a retinue list for the Adeptus Custodes, the Emperor's super badass personal guard.
My starting point for this list was "Space Marines turned up to eleven". The first draft was probably a bit over-the-top but thanks to feedback on the Forge Of War ITEN forums it's now a bit more balanced, but the Custodians would still give the Astartes a good arse-kicking mano-a-mano.
Check out the Adeptus Custodes Retinue List (docx format).