I just remodeled my 65X76 inch 1/2 bath into a full bathroom and every square inch was utilized. I'm sure others here will have better ideas, but you could follow a galley layout, with a 60X28" narrow bath with small, 24"-width shallow vanity (I went with this one, that still offers storage and a traditional look, with a super shallow depth of 11.5 inches for the console and under 19" for the sink basin). Then, put in a pocket door to a separate water closet for just your toilet. You'd still have almost 50" of space to work with in the WC. Here is another option, of a 'galley' style layout you could model. You will have less width in the 'walkway' but I think it's doable. Not sure about code, you'd have to check with your contractor.

Westchester Bathroom Renovation · More Info

@mdln The greek tub is amazing!!! It even has whirlpool option. I probably will get this one!

I want one, too! During my build I really wanted a Japanese soaking tub. When I showed it to my builder's designer, she said it looked like a big pot to cook people in (her experience was not custom homes). Unfortunately, the ones I looked at were twice this price. Had I seen this one, I would have it. My house is not even done (however, the BR's are) and I already want to rip out my tub and get this. Please keep me updated, would love to know if/how it works out.

Connie, not sure how that tub wll work for you. It's shorter, yes, but its actually wider than average tubs. It's 32 inches. You need a minimum of a 30" tub, iif you only have 51 inches of total width. You can go longer, but not wider. Unless I'm missing something.