Driving through Oman (Muscat)

Hello everyone!

Mi partner and I will be visiting Oman for a couple of weeks.
We thought of driving around from Muscat to Salalah along the coast and then back through the mountains. Then someone told us roads are quite dangerous and we'd better fly to Salalah...

Also, i was wondering whether, when driving, it is allowed/safe to just sleep in the car at night when driving in the middle of nowhere.

Lastly, are there any businesses you'd recommend for outdoors exploring, like sleeping in the desert or navigating a river?

Thanks a ton for your advice!

Happy travels