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.
I had one who was a beast. Level 55 but got her to 140 when I encountered a rex. After a short runaway I managed to kill the rex. Then on the way back to base a bear killed us all. - Note to self... Avoid bears
A must tame because they are a mid-game mount and usually platform mounts are mid to late-game. So be sure to tame one but note: They run out of stamina pretty fast so I suggest you pump stamina into it.