Not a giant fan of windows behind the range, but it is what it is...so...most exhaust fan manufacturers and range manufacturers have determined the required air flow (cubic feet per minute - CFM) as well as the optimum distance from top of cooking surface to bottom of hood. Start by checking the specifications for CFM and distance from cooktop with the range manufacturer. Not sure of your location, but here in the States the IRC requires exhaust fans for kitchen, bath and laundry. Some areas, although they have adopted the Code, do not enforce it. But if broiling pork chops ever happens at your place...you sort of want it.

Love the blue carpet. It's such a nice colour and you rarely see blue carpet!

Possible suggestions if sticking to same floor plan and hands firmly glued to the budget Leave the stove where it is. Down the side of the stove securely attach slimline fireproof panelling to the height of the oven's back control panel and the depth of the oven. Floor to ceiling if you prefer then if you wanted to you could change out the door itself, that is put the door handle to the right of the door so it swings back flush with the fireproof panelling. Put the dishwasher under the stainless steel bench top left of the sink. Take all the cabinetry out where the dishwasher is currently housed place the fridge in the centre of that wall building functional cabinetry around it. Get rid of the cupboard at the end of the stainless steel bench replace it with a wheeled butchers block the same width and depth of bench also have hinged sides so you can get extra useable bench top surfacing. You could then wheel it around include brakes on it of course so little hands don't go racing around with it.

Thanks for your comments everyone. We've taken your advice (Luke and NH) and changed the island to a rectangle (1200 x 3000). We lose one breakfast bar seat but gain storage and dining room space plus it shortens the distances from the island to the cooktops. It also removes the need for a corner carousel. We're much happier with this result. Dairy_maid, we've done what you suggested and walked through some common tasks. Overall it works reasonably well although we may keep some coffee spoons and butter knives in the scullery drawers for morning toast and coffee. We've also invested in a "silent" rangehood which has the motor on the outside of the house behind the fridge and we've upgraded the scullery sink to one that is 600 x 400 (internal size). Fabrication starts tomorrow. Woohoo. Once again, thanks so much for taking the time to respond. The design has been significantly improved with your input.