Both CCS and Flat Pads uses the same foam colour and type. The chart on the right is missing Purple, Green, and Blue's. Purple is more aggressive than yellow, Green sits in between White and Black, and Blue is between Green and Black. These are supplementary pads for the user to fine-tune their cut. So it goes Purp > Yellow > Orange > White > Green > Blue > Black.
CCS: The dimples hold products better, meaning longer working time and further spread (cover larger areas), not only that, it cuts cooler and (pockets) releases polish slower without being absorbed into the pad too quickly.
Pro Tip: You can release more products from the pockets by applying more pressure when you see fit.
Technically the pad has less surface (friction) contact than Flat pads, so that also means less "pad skipping/pulling"; Rotary polisher users will know what this means, the polisher pulls you around. With the pockets, the pad will 'float' better.
Flat: More contact area. As mentioned above, CCS has reduced surface contact, meaning it's less efficient at heavy cutting and heat generation. Heat can be good or bad, if well-managed, it aids in cutting, that's actually one of the attributes of microfiber cutting pads; microfiber generates and sustains heat better than foam. But too much heat can collapse the foam structure, cause delamination, dry up polish/compound prematurely and create more compound haze. But Flats are indeed more efficient pads.
Why does heat create more compound haze? Heat softens paint, and grit can dig into it and cut more than it's supposed to.