Our house sounds similar to yours. Our kitchen connects with our familyroom, too. Our kitchen cabinets are dark cherry & the granite is Giallo Ornamental. The floor in the kitchen & familyroom is white oak, finished in a medium brown. Our fireplace hearth is the same level as the floor. We used a brushed cream marble on the surround & hearth, so the finish is matte. The fireplace mantel and the wood around the fireplace are Navajo White---about the same color as the marble. We like the cream marble against the cream color wood. We considered using a brown marble for the surround & hearth but were concered that it would give the overall appearance of a big dark hole in the fireplace area.

Same product your using for tile.

Others will have better suggestions, but I can't imagine stacked stone looking appropriate with an antique fireplace. What is the style of the fireplace? Victorian? Craftsman? Georgian? If you have an image from the Web that looks similar, I think you'll find great suggestions here.

Generally, the tile replacement is done prior to the insert being installed, so that it all fits together properly, and the correct fire codes are followed. You will need to uninstall the insert to do the demo of the tile, and then retile. I would not recommend a formal white marble tile around a rustic insert of that type. The more formal mantel also is not in keeping with the casual spirit of the insert look.