As long as there is nothing on the other side of the island that you would need to get to, the length is not a problem. Do you also have 48" of aisle space on the ends of the island? (If there is a table nearby, you need at least 60").

However, I would put cabinets on the ends instead of in the middle of the overhang. Maybe only have stools on one side. And definitely take advantage of the length by having two large equal sized sinks, neither directly in front of the stove. 2 dishwashers would be awesome, too.

IMO 48” is about 6” more than necessary and adds a step each time you move between the two, I have 2 sinks in my island one across at an angle from the fridge and the same across from my stove we both cook so my hubby preps and I cook so works well for us. I think if you do all the cooking put it where it works for you

Will your kids grow up to be chefs? Where will your plates, coffee cups, etc go? Will anyone ever need to walk behind you to get a dish or glass or help set the table, or will they have to walk around all of Australia to get it without being in your way? My in-laws have a setup similar to your picture with about 48" of space and I feel like I am tripping over them every time I am in the space. That being said, I live in a multi cook home (my husband and the older of the two kids both help out) and have always preferred more space than the 48" inches most kitchen designers recommend.

It seem what you have is a galley or one wall kitchen with all appliances in one walk way. If that is workable for your cooking style go for it, but .....I think an L shape kitchen with divided prep zones and a refridgerator out of the work walkway can work also with the sink between the fridge and the stove. But that is only my opinion.

A practical option would be to make dinner mentally while you are in the proposed kitchen with your family there with you. See if you like it. For myself I like to have separate areas where many people can be working all at once, be it family members I am teaching to cook or friends for a festive occassion. Someone making a salad, someone doing rolls or dessert, someone keeping ahead of the dirty dishes, etc.

If you decide to go ahead this design, I feel the bar sink shouldn't locate at the right side, it's better on the left side of your Australia, because you have stools and more sitting area on the right side.

Keep the long island with cabinets on the ends and maybe some drawers on the ends facing the stool areas for homework, crayons and kid clutter. I have 60" between my stove and main dish washing sink that are across from each other. It's a very comfortable set up for me, since I tend to wash dishes as I cook. I am constantly back and forth between the sink and stove for draining pots, filling pots, and other tasks. I prep everything prior to turning on the stove, so a prep sink a little further away would be fine for me. I would use it as a prep station and then bring all of my cut items to next to the stove.