The sink in the island is the way to go here. As Lampert Dias mentioned above, your island can be larger than drawn. I prefer the sink and the breakfast bar at the same height as pictured above, but some people like to step the bar side up to protect it from the sink. It is an option. You can put the pantry and refrigerator on either side of the wall or even split them up and flank the wall as long as the refrigerator door can open. I would take the opportunity for more storage or display and put a cabinet on the wall behind the breakfast bar. Consider using a shallower cabinet there like 17" deep. It could be like a "china" cabinet display piece or more pantry storage if needed.

Where is your refrigerator? If you move your stove over is there room for a refrigerator and a stove? You will need at the very least 12" on each side of your stove. Your sink can either go by the window or on the island. Another option is to put the stove on the outside wall and move the window over. If you do this you can put the sink on the island. The refrigerator can go on the back wall and you might have room for a 24" wide pantry at the end next to the door and the refrigerator can go next to the pantry.

I'd put another set of sliding doors between the lounge and the playroom rather than a solid wall. Reason being is that it gives you more options. You get to sequester the mess and noise when you want and you still get a good flow later on when the kidlets aren't such mess monsters. I'd make both sets of sliding doors have full-length frosted glass inserts. That will let in the light. Or you could use shoji doors if that suits the decor better. From your plan, I'm assuming the house is semi-detached, so windows on the right wall aren't possible? Also, you might consider a pocket door from the hallway to the lounge and from the hallway to the utility room. That way you don't have to allow space for door swing.

We are considering getting a glass back splash for our new kitchen but are unsure regarding hard wearing or do they crack over time esp with the heat from the cooker. Also any recommendations of good suppliers in the Dublin area. Thanks