Looks strange... I prefer a spoiler/wing to be mounted on top of the boot/trunk rather than on the back of it.
Maybe instead of criticizing someone's work, how about you use constructive criticism to help them so they know where to improve.
redid rollbar, added carbon flares, colored rollbar and inner back thing dark gray to match the flares. Before: After:
The previous pictures look like the jbeam was weird or you had crashed as the wing and diffuser were bent in unnatural shapes.