When we remodeled a bathroom that looked similar to ninigret's picture, we removed that cabinet (it had a door, went all the way back, and was useless for anything but storing toilet paper). We pushed the new tub back to the right-hand wall, and had a tiled ledge at the foot of the tub on the left. Great place to store tub toys and have soap and shampoo handy. We also had a wall niche.
I appreciated having the toilet next to the tub, not the sink, for hanging out on when the little kids needed me around but not holding on to them in the tub.
I also changed the door so that when it was open, it didn't block the view of the tub and so I had more room inside the bathroom. We actually changed it to a pocket door because there was no other option.
In our new house, the kids' bathroom came with two sinks on a long vanity. We have two boys, they only ever used one of the sinks. Seriously, one sink is continually dusty because they never, ever use it. There's a single bank of drawers between the two sinks and a medicine cabinet, and I wish we had more drawers instead of two sinks with cabinets beneath.
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Master suite layout
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