You should be able to get everything that you want ........ Are you going to have a cabinet maker build it for you ? I suggest that you work with them and have them draw it up for you........Most cabinet makers are very good at working with their clients to get them what they want.

Mubashira, Kitchen chimney size should be the size of stove or larger than the stove. A bigger chimney covers a larger area. Please also look at important parameters like suction power/ noise levels.

Totally doable as long as the island is not too bulky. And of course if the circulation space around the island is at least 3'-0" wide. You don't need too much space to move around in a kitchen because you should be able to pick up a hot dish and put it down on another surface without having to move too much. 12'x14' is a large size and a work island would possibly make the space more practical to use. In the pictures attached, the work island is only 2' wide but 4' feet long

However, it may not be available in your desired colour. For the custom finish we may have to get exterior shell fabricated. Thanks, Nitin Cornerstone Designs, Bangalore.