2010 Prius weight and storage

Hi

Going to try and keep this short and succinct, family of 4 , 2 adults and 2 kids, one prius
Want to go camping and riding bikes
We have a hitch and rack for the bikes but basically over bumps and roads that are uneven sometimes I hear scraping
That is with just the passengers 4 and 6 yr old and 2 adults plus their bikes
To get the job done we need a roof rack and the bikes plus hitch+rack on the back
Really concerned about the overall weight and damaging the car

So what can we do.. love the car.. but how can we make this work? Can anything be done with the suspension, don't mind spending the $$$ what is the best option, can we lift the car up ? Stiffen the suspension some how so it doesn't get so low. We are not big people the roads here are decent.. But sometimes the clearance just isn't there.

Thanks for your thoughts!