I've been thinking a lot about this over the last hour or so and I have decided whilst i plan on having a core force of Red Hunters to add some spice to the force I plan on having some marines from the Mentor Legion join the party!
First up though the important thing, who are the Red Hunters? Well there is some good info and images linked here:
Now as you can see their "just another red marine force" but the whole link to the Inquisition is too good a thing to waste, plus from other sources you get some awesome hints like this:
An Elite Squad - 5 man veteran squad - all with some pimped kit
A figure in the command squad - possibly master of the fleet as an advisor, with some boosted comms etc
At least 1 Deathwatch marine in a forthcoming DW squad, or maybe a terminator or two depending on what future rules we get
A Body guard (along with a Red Hunter) in my Inquisitors retinue
There are two ways Imperial commanders use them on the battlefield when they are loaned to them. First the cadre element may simply be used as a powerful squad, gaining the benefits of their special equipment; alternatively, they may become leaders for other units. The latter is preferred by Imperial Guard commanders as the Elite Cadre make especially good leaders for units of normal warriors."