I see what you mean, your backend has lots going on and I am not sure what it is all about.
I like everything you have done, not knocking it at all but something is just not the icing on the cake yet.
Go carefull doing this as there are many sharp bits poking out on the rear panel
The mod does make the rear end look better though but not sure if his car is any faster than before we also removed that counter weight bolted on the inside of the tailgate.
Replaced the Y pipe for a Evny one and then got a Scorpion fitted. Left the backbox off and drove home then done the bumper tuck which took 2 minutes. Just drilled and screwed using the 2 tags either side higher up so it can be reversed without any damage to the bumper showing.
Then refitted the backbox and the result is perfect. Love the sound and the look