We also have created an enormous amount of useable space by re-arranging what was available. It is amazing what can be done by judicious installation of dividers and shelves. Our Jayco 21J came with tiny plastic trays, which were functioning as drawers. They wer mounted on aluminum sliding tracks. I replaced those with baltic birch plywood drawers, which at least doubled the usuable space.
Peter
Jayco Jay Feather 21J
2007 Ford F150, 5.4L, Reese Dual Cam WDH, Prodigy Brake Control, Honda EU2000i
Most of my cabinets had room behind the false backs, so I moved them back. We do not use the shower so I installed a clothes rod there. Added wire shelves the original clothes closet. I stack clear shoe boxes or bins under my couch and cans organize things better. We will also remove stuff that we thought we needed, but never used.
We also took out dividers that kept us from usable space. In addition, DH put pipes into the storage area, but up high, to hold poles, broom, etc. Many, many plastic storage boxes keep things organized. New shelf in under sink cabinet just 3" below existing shelf and now a space for platters, cutting board and griddle. Shelves in closet instead of hanging space. We even made a "wine cellar" using a cardboard wine box with the dividers in it. Wine travels safely and there is (sometimes) room for oil and vinegar bottles, too.
Glad to see that another camper does not use the shower. We camp almost exclusively in provincial parks, which have excellent showers. Since we did not use ours, I took out the entire tub/shower arrangent. I made a new top for the sink, which goes all the way across. I am now working on a new undercounter cabinet and, may-be, a storage cabinet to the right of the little sink. Lots of space.