Tile with a natural stone, slate, or terra cotta look would all work for your country kitchen. Don't worry about darker colors... I don't think it'll significantly reduce the visual size of your space. Dark colors have such a bad reputation for "making a room look smaller", and as a designer, I think that's BS. Far more important than color is the wet/dry slippery factor (COF) of the surface. READ THIS PAGE (
http://www.daltileproducts.com/factors.cfm?factor=2 ), particularly about glazed tiles and water spillage. If you go to Habitat or another used building supply warehouse, be VERY CONSCIOUS of what the tile finish is, because you won't have the mfr's information available to you.
Definitely go with darker grout.
And make sure your installer actually knows what they're doing. My old landlords had a guy come in to do my apartment kitchen (he laid tile on hardibacker on hardwood, on the 2nd floor), and the guy was a tile layer's assistant, but he still screwed up the job, and there were spots where the tile completely released from the backing, came up, broke into pieces, etc. It's a mess.
Good luck.
Edited to Add:
Tile floors are far more harsh on your dropped dishes and glassware than vinyl. ANYTHING you drop on a tile floor will break, whereas with vinyl you get the occasional reprieve (tho usually only with heavier coffeemugs and stoneware, but hey, it's something.)