I use my paracer as my cargo transport dino for short to mid distance. I use it to go to the redwood nearby and gather MASSIVE amounts of metal. Just hop off, get the metal, load up the paracer, then get back home. They can defend themselves quite effectively
The only dino that'll agro an unconscious paracer is a Rex. So if those are taken care off and your cautious about not bringing in extra friend with you. You don't have to worry about other creature damaging your tame.
On Scorched Earth the Paracer with its platform saddle is a needed tame. You can put a cannon on it and use it for taming Rock Elementals or use its high weight and health for carrying large loads of supplies around through dangerous areas.