I'm still missing something here, if you have a problem climbing in and out of a tub, wouldn't you have a problem STANDING in a shower? Wouldn't you need a "sitting" tub. One of those things that sit across a tub to make a seat? I've been lucky in that as my family ages they age well so I haven't seen a lot of people who are well enough travel but not well enough to step into a tub. It was just a thought about space usage.
That walk-in shower on the Mariner sounds interesting to me, tho.
