Welcome to the forum!
I think Zordo does suspension and you might want to get in touch with him, from what I've seen he won't muck you around.
I don't know if Unichip do a chip for the '22 but ChipIt certainly do and Robert would be well worth talking to. Definite power increase - just remember that power has to come from somewhere, and most of the time it's extra fuel.
The big trick with diesels is to enjoy the journey, rather than win the race. If you change your perspective, and just let it do its work, it'll get you there reliably. We tow our van everywhere - we're camped in Coopernook right at this moment, I'm sitting at the dining table in my van right now tapping away. Barely broke 100km/h downhill on the way here, most of the time sat around 90-95km/h and the car just purred along.