That's what I was thinking too. The profile of the original Maverick is too big in the body with a 1/4" long barrel. Adding the longer, bulky barrel assembly balances out the shape considerably. Unfortunately, it's pretty long now and would be difficult to holster.
This was a prototype, I'd like to be able to find a way to make the barrel attachment removable since it's currently attached to the gun body with Bondo fiberglass jelly. The stuff is really strong but I worry about it cracking and breaking off. I also want to try Gorilla Glue, but that would require me to sand and shape the flat surface of the barrel attachment to be perfectly smooth and flush with the Maverick body's surface, and then clamping it together while the glue dries.
If there's enough interest, I'll definitely make myself one and a few more to put up for sale.