I've had a think too (thanks to your thoughts @caitlinfurby). Would it work if the bath went down the end beneath the window (handbasin/end of bath currently there). The toilet stays where it is but the wall reduced to a pony wall. The linen cupboard on the right hand side as you enter the bathroom is removed, as is my sons bedroom wardrobe (a new wardrobe for his room can go on the wall in his room against the hallway). That new space is turned into a walk in shower. The cupboard on the left hand side can be widened a bit at that current entrance way to make a new linen cupboard. Around the corner from that, opposite the toilet could be where the handbasin goes or in between the bath and shower? The door can be a pocket/cavity door or just a barn style door to enter the bathroom off the hallway. The current door to the kitchen is actually hinged the other than the plans show but we could just re hinge it the same as the plans show. The first little box area on the plans to the right as you enter the kitchen will have to stay as that is where the fridge is. The window at the end of the bathroom is close to going all the length of the wall...don't really want window sill getting wet from shower hence why maybe bath could go there. Husband wants to have a separate bath and shower. Do you think these ideas could work? Means the plumbing can pretty much stay as where it is too. What to you think??

something like this may suit without altering the plumbing too muchor this arrangement adds more privacy from the living area, has the bath in the main bathroom, a bigger shower in the ensuite and more space for mirrored wall cabinets and a fixed "window" above the mirrors could add extra daylight between the bathrooms

I have decided that it is a bit extravagant for me to have two bathrooms in my little house based on the small amount of times the second bathroom will be used. I am still wanting to have a laundry cupboard that has the washing machine and dryer in it (and maybe some storage or bench space for sorting????), but where the top bathroom was, I am just going to have a walk in robe off the bedroom to the right. It will have a cavity sliding door into the walk in robe. The walls go to 2700mm. To enable the shower to have a width of 900mm in the lower bathroom, the doorway is now going to be moved so that the entry to the bathroom is via a door to the far right. The toilet will now be in between the shower and vanity, so that the toilet isnt the first thing you see when you walk into the bathroom. Can anyone see any issues with the changed design, and can you suggest how to design the walk in robe and the laundry cupboard to maximise storage and function. Should I now make the the bathroom deeper and the walk in robe narrower? Should I make the laundry cupboard wider? PS. If I ever buy another house, it will be one that has already been renovated.....I am not made for design decisions. Thanks in advance for your help.

@oklouise thanks for measurement suggestions, good starting point with so many choices available. About the bath, we thought just a freestanding, or back to wall bath, would take less space compared to drop in bath. But it something worth considering with the suggested layout. Also, the bathroom entry door would be sliding cavity if that helps. @differentways thanks for a suggestion that we haven't really thought about. We have considered a smaller Japanese style deep bath, but obviously this would not be practical for kids. Just to make sure I understand your concept, you are suggesting a purpose built bath which will be about 2570mm (including the ledge), husband thinks this is very generous :). My husband and I can't find a photo of something similar, do you have a link? Are you suggesting the sides of the bath to be a lower height compared to standard bath? I like the idea of a ledge, would definitely make bathing kids easier. About the position of the ensuite, do you mean placing it outside the bedroom area so it can be accessed by others? We have discussed this, still part of ongoing discussion. If need to we just have to move the bedroom entrance door. I have attached a google earth view.