I had a hard time finding a perfect square sink to fit in an 18" base for the prep sink on our island. In the end, we picked a 16" round sink for couple reasons. First, it fit. Barely. Second, our kitchen is full of lines and few curves. So this was design statement. Third, we wanted to put this on the corner of the island and have it accessible from either side of the corner. Since the square sinks out there weren't perfectly square, I didn't want to go that route. We bought Grohe Ladylux 3 for both the main sink and a smaller version for the prep sink. Plenty of curves. Here's the sink, w/o faucets installed yet. Here is a link that might be useful: Our Bungalow and Kitchen remodel blog

I don't like Corian. My sinks don't feel like plastic or corian. Yes, it is a composite material, but I'm not sure somebody would walk up to it and say "ooouuhhgg it's composite." They look metallically, silvery gray and wear like iron. If your mindset is that composite equals fake, then they aren't for you. Frankly, sometimes composite materials are better, IMHO, than natural. YMMV. And this is coming from someone who makes the huge majority of her food from scratch with organic and locally-sourced ingredients so natural matters to me. My cabinets were made by Cornerstone Cabinetry, a one-man shop in Buckley. His quote equaled or was better price wise and included much more than quotes I received elsewhere for semi-custom cabinets. My cabs were made without fillers and included end panels without extra charge. I received personal attention, hand holding, and patience with last minute changes as the cabs were being made that I doubt you'd receive from a big box store or many other places. After experiencing a custom shop and products, I can't believe I would have been happy with anything else.

I like the first picture over the second. I just installed 12"x12" natural black slate tile with a 6"x12" border in my kitchen. I put it on a diagonal. If I were using your size tile, I would do the running bond across the room rather than the length of the room. I also used a dark grout, charcoal rather than lighter grout. I had to use a transition strip because the proper underlayment raised the level of the tile enough to require a transition strip. You may have to do the same. It's not the end of the world. It protects the tile and wood floor and provides a visual cue that the level is changing. We don't even notice it anymore.

My kitchen sink is the Kohler Whitehaven "short apron" style. It can be installed easily on a standard sink base cabinet. Since I kept my cabinets, I went with the "short apron" style so i would not need to get a new sink base cabinet. I like the short apron style because it is somewhat reminiscent of the big cast iron sinks from the early part of the 1900's, and I was going for a vintage look. The Whitehaven also comes in a "tall apron" style which needs a farm sink base cabinet and more resembles the "butler" sinks of Europe - which is what the farmhouse sinks are modeled on. Both the short and tall apron sinks are the same depth inside and made of cast iron. I really like mine, not just for how pretty it is, but I like being close to the sink while I work, and despite being close, I never splash myself like I did with my old sink. I probably prefer the table because I'm short and don't like dangling my legs:) I will add that my sink fits the 36" cabinet base - it is plenty big. It comes smaller and if you wanted a few more inches, you might do a smaller sink base cabinet if you could get it to fit the dimensions.