if you do consider the putz, look at replacing the floor beams and screws with way more thinner and more frequent traditional riblet like cross ribs. The more rigid putz floorbeams transfer impact loads directly to the screws on the side truss flanges and could thereby more easily damage a prime structural member.
Aside from the flexibility you gain a heck of a lot more room AND much more stability - gain all around

consider not putting on rub rails - they will hack the crap out of your knuckles if you try rolling. may even make like a scissor action w/ your pinky against the rocks or yr buddys yak with or without rails - cut off versus just mashed.

another issue is skin load transfer will be less w/ the more rigid truss. So i wonder if this is the case if it would be more parallel(to using the skin as in traditionals) to remove all the side truss diags, run the rib up from bottom flange to top and adhere the skin so it(the skin) provides the cross bracing all around. but use all flex joints to reduce damage spread.

(the top and less on the bottom of traditionals looks like just an orthoganal truss for horizontal deflections and also uses flex joints so just something like that but vertical too- but lap rather than mortise too keep strenght and flexibility up)

the idea of seams lining up w/ the sides then makes some sense.

the books i remember on traditionals all place the cockput ring directly on the ctr of the cross beam directly in front and the one behind. therefore any stress even on traditionals is placed in the exact centre or weakest part of the beam . If the putz uses otherwise and places the load other than the centre of these beams it may be slightly stronger approach.

anyway, look at modifying the depth,attachments and number of the few floor beams.

-mick