I know that this is pretty simplistic - I'm sure that the Color Management forum people would be on my case for this reply. But, when we profile for offset proofing, we shoot for GRACoL ink densities of C: 1.45, M: 1.45, Y: 1.0, K: 1.7. If you want more pop in images and don't care about matching printing press sheets, these values can be increased as long as you aren't putting more ink on the sheet than it can handle. We read maximum ink densities for the PRS this morning, and with Photo Black ink, we got: C: 1.67, M: 1.72, Y: 1.29, and K: 1.48. With Matte Black, we got a K of 1.91. So, this sheet has a much better maximum Photo Black density than matte sheets, which would generally fall in the 1.2 - 1.3 black density range using Photo Black. But, black heavy images would have a much more dense and richer look with Matte Black ink (but the matte black ink would dull down the satin finish, too, I would guess).
Re. using a CMYK profile for RGB photography, the CMYK profile that you would build with a RIP is the output profile, so it applies standardization to the printer output. If you are sending the RIP an RGB image, then the RIP can assign an input profile, like Adobe RGB, or sRGB or ProPhoto RGB to the image. I remember talking to a printer on the West Coast a few years back who was using the ColorBurst RIP, building CMYK profiles for their printers to get predictable output, and using ProPhoto RGB as an input profile to get knock out good photographic prints.
Tony