Dude, from what you're describing it sounds as if there's a huge amount of flex when you drive off the street and onto your crossover to your home. I know there's a degree of body/chassis flex inbuilt into all vehicles, more so with vehicles having a body-on-chassis type build, but the Aurions are all monocoque, so the degree of flex you seem to be describing is VERY concerning at the least. The way you describe it, I'm picturing a very wobbly flexible monocoque shell which bends and twists over every bump or uneven surface. This, to me is symptomatic of catastrophic failure somewhere. The "knocking" of the windscreen sunroof may well be indicative of a more serious problem. Are all your doors opening and closing smoothly? The bonnet, the boot? Hopefully it's not rust eating through to the monocoque shell, and it's happening somewhere where you can't see, or not very obvious. Sorry, don't mean to alarm you but, yeah it's either that, or (hopefully) just some relatively minor bushing issues with your suspension.