I'd ditch the rear seats and angle the rear top portion forward more. Safer and more eye appealing.
The rear seats are neat but look scary to me. No full on harness, I'd hope you only plan to use them in very light conditions. No support, looks like someone could get tossed around real good in those.
And I'll do the Pirate thing, needs triangulation. Cage is nice but needs more triangles to be really strong.
One of the better looking truggies I've seen. Tapering the rear will give it a hummer-esque look.