Greetings!
hmmm… Well with a B+ you gain a little width, but lose the cab over bed. That cab over bed can provide a ton of extra overhead storage…
One of things I really like about the Class C’s vs. the Class B’s is the number of people they can sleep, and the living area. For me, I really like a bed that’s permanent. I don’t want to have to convert a dinette or a sofa into my bed every night. Some of the Wayfarer’s seem to have a rear bed, with a sofa/bed across from a dinette/bed up front. I like that because you have a permanent bed plus a nice living/dining room. That also gives you extra beds for company. Either the dinette or the sofa could probably be switched out for two captains/lounge/recliner chairs with a folding table between them too.
Most Class C’s are also built on heavier duty chassis, with better brakes, suspension, etc. They also usually have duallies in the rear which can give you much better traction when needed.
I like buses, but don’t like to recommend any DIY projects to newbies because without experience it’s almost impossible to know what you really want & need. It usually leads to lots of builds, lots of frustrations, and lots of needless added expenses.
If you’re comfortable sleeping on a sofa (I am), a layout like below my tempt you. I just leave my sleeping my sleeping bag on my sofa (futon sofa/bed in my case) all the time, and have other comfy seating.
https://www.rvtrader.com/listing/1997-Chinook-Concourse-5019850872
Cheers!