The [Safety First: Look Ahead Design Strategies[(https://www.houzz.com.au/magazine/safety-first-look-ahead-design-strategies-for-a-future-proof-bathroom-stsetivw-vs~32118909) article says: "A bath is not essentialUnless you are wedded to a good wallow in the tub and have the space, Barnes recommends increasing the shower area instead. “In actual fact, sitting under running water is more beneficial for circulation than soaking in a tub.” A shower space big enough for two, should assisted showering become necessary, is a growing trend." So I'll keep looking for a soaker bath (not renovating until the end of the year) but also start planning a luxury large shower area. I like the idea of a choice of showers, seating of some sort, and completely separating water and electricity. One of the things that annoys me about the current layout is the shower immediately in front of the door so you are inevitably walking across a wet floor to wash your hands or get an aspirin.

Couple of observations Lots of mosaic tiles have sharp edges so you need to be very detailed in how you do this. Have you considered a corner (spayed front) shower bath combo. There are several manufacturers that make these in fibreglass and acrylic materials (some with spa jets also). That way you can consider a shower screen that would be integral.

4 X 3.3m is a great sized space (bigger than our family bathroom, anyway!) I found the Reece bathroom planner a good starting point as you can gain a 3D view of the plan and it is fairly simple to use. We have decided to create a wet room sort of space at one end of our room (shower adjacent to bath with a single screen between shower and the rest of the room) so that the bath/wall behind bath can be a feature. Something like this photo or see my bathroom idea book

within a budget and available space the best option is to retain the existing floorplan and use a deep handbasin for both laundry and handwashing... i'm not aware of any legal reason why you need a basin and tub in a combined room so curious about that advice...but other option could be to combine the laundry in a kitchen or on the wall outside the bathroom enclosed in a cupboard but can't be specific without whole house plans and more info