I always use integral color for appearance jobs. In general, even if I am just using some lamp black, it evens out the color of the concrete and tones down the glare. I prefer to use tans, and the issue ends up being that tan integral color, runs with a red tint, that red tint fades after a few years. This does not happen with stone, because of the amount of iron in the stone. Unless you are prepared to go nuts, it will be very hard to match that stone you already have, as you will find that even it has faded. I would recommend going with a standard medium broom finish, and using an integral color that you think is one to two shades lighter than the color in your stone. It will complement, not match, the existing stone. It also creates a nice demarcation between the kitchen and the pool deck, think of this as separate rooms. Normally, you would not have the same flooring in your living room as your kitchen.
I like to score concrete in geometric patterns, or in random arcs. If I do a geometric pattern, I do a grid, with the lines equal distance apart, with a 12" band around the edges. Essentially, this gives a look of 30" square tiles, of sorts. I have seen some great stamped jobs, that held up well, but, it takes a real craftsman and artist to do a good job.
I'm feeling bearish, and I'm packing a Wusthof Grand Brisket slicer from MABA
"I'm Armenian...perhaps...but then again...maybe not..."