also will give illusion of a bigger bathroom if you use bigger tiles ..I used small ones on one wall as feature wall and larger ones on other walls ..

It can either look really dramatic or too dark, depending on the size of the room as well as your other components. I've attached a couple of images of our work using dark tiles, the smaller bathroom we have surrounded the bath with dark tiles but then balance it with an extra large mirror to bounce the light around the room. The larger bathroom we have taken the floor colour way onto the wall but used a different texture on the walls for drama. Hopefully this gives you more of an idea but you shouldn't to nervous of the room being dark, it's where you can create a contrast as well as textures. Look forward to seeing what you go with in the end.

Yes thank you for your thoughts. the room is 2.8 (with window) vs 3.4m. I do find it a bit annoying too as I don't like that you open the door and see straight away into the shower (though I'm certain the door would have a lock). I'm sure they lined the bath up to be with the window as visually that looks better, but then I find the space at the end annoying. I like the alternative drawings (I like three of them lots!) and I had been considering an drop in bath built wall to wall rather than a freestanding but also finding it frustrating to find a really nice supportive bath and there are less drop in baths than freestanding around at the moment which is a bit annoying. Thanks Anna for the picture, that helps as that looks good (though we would have more space at either end, 50cm) and I prefer the look of yours with some space but not as cavenous... I think I might have to have a talk with my husband as we really need to work out what to do!!

I would prefer to keep the WC separate to the Bathroom as you have 3-4 kids? who will get bigger very quickly, having a powder room downstairs won't help with the morning rush to school., But it's your house so I have added a pocket door between the WC and Bathroom. I have also taken that small robe space for an extra vanity in the WC/Powder room. No width dimesion given for the WC The ensuite could use that extra entrance space as a sit down makeup and hair bench for your wife.