I've been very slightly considering trading up from my 6X12 to a 7X14 for only one reason. That is to have an extra foot of length on the bed with the frame/mattress sideways, across the trailer. It "just fits" with my 6X12 since, luckily, I'm 4 inches shy of 6 feet tall. (OK, "short."

) However, I do enjoy the compactness, lighter weight, single axle, easy-to-fit-in-smaller-spaces aspect of my 6X12, and for now that outweighs the comfort of another foot of bed length.
There's a ton of floor plans and layouts on here, just about every configuration you can dream up. Mine is just one, and though planned as adaptable for cargo, I really only use it for camping/fishing trips. Its my home away from home, and I like it better than the 'residence" home for sure!