If you could make a pocket door instead of a slider , you could use that entryway space.

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.

windows in master bedroom need to allow views and privacy and much as i would prefer bed on NE this keeps the bed in view towards and from family room so prefer bed on south wests wall and small sliding doors pushed towards north side of room with tall narrow window beside sliding door and highlight window for light with privacy and wall space for chest of drawers...acknowledging theta the pwdr doesn't have a window but my suggested arrangement uses less total space more efficiently and is better for older kids and long stay visiting parents (more people can use the various options at the same time) and a small ventilating skylight will exhaust and brighten the toilet and vanity area ...the wide door into the lounge can be a stacker or stable door so you need to investigate local options (and everything is expensive unless it does what you want...we always use solid core doors that can be ten times the price of a basic hollow core door but love them so we economise elsewhere) and barn door between entry and family would be OK as long as you like them and it doesn't compromise lounge doors but could look ok if both doors are the same style and different widths...and location of dishwasher is personal and if you have already been unhappy with sink in main kitchen then have it in the scullery...main advantage of my suggested kitchen location is that it's closer to the front and the family area and external doors and the pantry uses the central space that can be much better illuminated with another ventilating skylight instead of a tiny external window and noisy exhaust fan

I'm looking for a door lock suitable for a cavity slider that can be locked/unlocked from either side regardless of what the other side is. Sounds confusing???? Let me try and explain, and please see attached photo... we have a cavity slider between our main bathroom and our guest room (Bedroom 4), like a Jack n Jill bathroom or a Poor Man's Ensuite as they're sometimes known by, and I need a lock for it so that if there are guests they can have the door locked from their side but if someone else uses the bathroom it can also locked from that side.