XC60 AWD pitching when towing caravan.

[LCFC_man]

Our Volvo 2017 XC60 2.4 D5 AWD (Polestar tuned) has plenty of power/torque, and tows our Elddis Affinity 530 easily without any hint of swaying. However, I do find that there is quite a lot of pitching/bucking, particularly on more uneven roads. We didn't have the adaptive suspension fitted when new (possibly a mistake ☹️), so it has the standard suspension. Reviewing forums, I've also been careful to load the nosweight to approx 90kg, taking care not to load much behind the axle. Even with this balanced loading there is significant pitching. I'm considering fitting some auxiliary progressive springs (eg MAD) to see if this could reduce the pitching. Has anyone any thoughts/experience on this issue?