Okay. So I will explain the reasons for wanting to renovate this small bathroom. Again. For those, especially Tarheel Terp, who doesn't seem to get the purpose behind this

In 4-5 years when we move into this house my husband will be 65. I will be a few years younger.
What we don't want to be doing is climbing in and out of a bathtub when we are in our 70's and 80's. Bleeding obvious I would have thought.
Nor do we want to have to renovate a bathroom when we are living there as it is the only bathroom in the house.
So. Quite simple really. As it's such a small bathroom we want to remove the bathtub and replace with a decent size shower. One that will take a chair if necessary.
As I said in my initial post we can bump that wall back about a foot.
Any 'helpful suggestions' on the layout would be greatly appreciated
And cibula11 the floor is wood. We should be able to use the same drain hole as the tub has now.