Anybody able to give advice on upgrading suspension on my 2007 2.0Tdi Passat Estate?

It has standard 16" wheels, and suspension is a bit soft for the caravan I tow. At 75Kg noseweight in the van it still scrubs the mudflaps on the slightest dip in the road surface.

I was wondering about how to fit something stiffer?

Thanks for any advice available.

WAB