I am by no means an expert... But that (Bath and a half) was the feature that SOLD! both my wife and I on the rig we bought,,, A Damon Intruder 377w
I'm sure it's not the only bath.5 out there but I can tell you already I've been happy with that 2nd toilet
In this rig the rear is the master bath, RV size mini-shower (too small) Dual wash basins (Wish they had made the shower bigger at the expense of one of those basins) and Macerating toilet (It pumps the "stuff" up to the middle of the rig with a macerator pump) Sit, think, wipe, push button, and it does the rest. Does require 12v systems be active
Moving toward the front is the master bedroom (Queen size) dual slide out (Bed/Wardrobe)
Moving foward is the hallway, closets on one side, power and control center on the other
Moving very slightly forward (behind the power center) is the half bath, Sea-Land type Toiled (Regular RV kind with pedal and sprayer) nothing special here, black tank is under your seat as you think here,
Moving forward is the dining table (I have table, not "booth" and the start of the kitchen area
Moving forward is the convert-a-bed/sofa, which is the main lounge and a slide out, across the isle from it is the rest of the kitchen and the recliner which can't be reclined cause there is no place for it to recline to (nice leather chair though) just ahead of it is the entry/exit and ahead of that is the pair of captains chair and the motor hump.
Tv's front and rear, Onan 5500 below the dining table Power transfer switch in the half bath under the basin in the cabnet (found it when it fried under warranty) and lots of basements
Nice rig. if you'd like to see it's outside, Look up and to the left slightly, it's my avatar