You don't need the NKBA 21" minimum on All sides, only the side you are entering or exiting the tub from. On the other three sides I think you would want at least 4" between the outside edge of the rim and the wall so you could clean around it and easily retrieve anything that fell between the tub and wall. (Which is the purpose for the measurement for sinks that do not abut the wall directly).

Thanks so much for the suggestions and advice. I am concerned about being able to get the tub close enough for a faucet reach but far away enough to clean. Unfortunately, a floor mount is not ideal since we're on a concrete slab. A wall mount would be a much easier install. It would be on a wall backing up to the master closet, so I think we could also have a panel to access the plumbing. I really like the Newport brass fixture, although it's a bit more modern than fixtures we've used in the other bathrooms. I would like to use a readily available brand name so parts are replaceable.

Leftfoot, I have the V&A clawfoot 60" slipper tub and LOVE it. It is not an inexpensive tub, but it is also one you will not regret. Getting use to it from a garden cultured marble tub was the only thing. Because it is more narrow, it takes a lot less water to fill it. My hubby who is 220, son who is 6.1 195 son and I love it. Son likes it better than the standard tub in his bathroom. The one thing you cannot do, because it is not cast iron, and is a stone resin, is sit on the side of it. It is only 122 lbs.

60” if you want to have any hope of cleaning around it without hiring a contortionist. Freestanding takes up way more space than a built in with a deck. You’d be better off with a built in with a deck. You have room to sit things. Like soap and shampoo. And yourself.