We have a 2012 Fun Finder 210WBS also made by Cruiser RV. It is approximately the same size as the Shadow Cruiser you are considering. We are a couple with a Lab mix dog.
We find the size entirely adequate for our needs. We often camp two weeks at a time and have no problem with the overall size of the camper. The main difference between our camper and the one you are considering is the kitchen prep area (yours is much better) and the slide (ours has a sofa no dinette). The sofa vs dinette is a personal preference. We like the sofa because we find it much more comfortable for lounging than a dinette. We eat outside as often as weather premits and use folding tables inside when necessary. I would suggest that you sit at the dinette for an extended period to make sure you will find it comfortable. As to storage, we find our small camper has more than enough. We have always been very focused on organizing our stuff and taking only what we actually need and use. We are also pretty dilligent about putting everything away when not using it. Because you are a boater I'm pretty sure you also follow the philosophy of "everything has a place and everything is in its place."
As to build quality: we are very satisfied. In four seasons of camping we have had only one significant problem. Our slide uses the Schwintek mecanism. The mechanism has worked well with no issues, but there was one problem with the slide's installation. Under the slide there are three nylon rollers that support the slide as it moves in and out. One of those rollers was so impacted with caulk that it would not turn. As a result the buttom of the slide skidded across this roller every time the slide moved. It went unnoticed until the roller began tearing up the underside of the slide's floor. I managed to dig out the caulk enabling the roller to turn normally, and I also reinforced the damaged floor with a sheet of aluminum. So if this camper uses the Schwintek slide I'd recommend checking those rollers to make sure they operate properly.