If there was a bathroom that could connect to the back bedroom (our daughter's room) and another bedroom (one of the new rooms), something like this seems compact and would add closet space. I think we would need a tub, though, and I am in favor of things that aren't so high maintenance (the white subway tile seems like a not great choice).
These two are from the same bathroom. We don't really have a master bathroom right now. Our bedroom is on the other side of the house. We talked about maybe making one of the new bedrooms a master and doing a master bath, but we like having the fireplace in our room, and it has a nice view, so we'd need to do something.
I like these windows
Storage, window seat, light
Lots of storage. Good use of space.
I love this window and window seat
This is similar to the other idea - of moving forward from a different space - but it uses one of the two existing spots as a starting point (instead of coming out from the kitchen) and seems to have three going forward.