Different runners prefer different running surfaces. I rarely run on paved roads because of the traffic. I've always enjoyed running on hard dirt trails. It slows you down a bit but it's easier on the joints. I like crushed gravel rail trails the best -- which is why my favorite trail on the planet is the High Bridge Trail in Farmville.
It's easy on the joints plus it's always in nice scenery. My gravel trail running experience is that it engages your muscles differently. You have to be attentive to terrain and foot placement. You can't always expect that the spot ahead of you will be safe to step on. If the gravel is too fine you can't get a good push off. I sometimes run on the local high school track. It's not particularly well-groomed (holes, weeds growing on it). And so it's usually gravel trails for me. Level gravel is basically the same as the street for me.
Today I got in 8 miles on the HBT.
It was hot and humid.
One thing I've come to accept about running in high humidity is just to accept it for what it is and not beat yourself up over distance and time. You have to hydrate proactively -- before you even feel thirsty. Don't worry much, if at all, about pace. Listen to your body. Maximize exposed skin to encourage evaporation. Make sure you have a good running hat to soak up the sweat before it drips into your eyes.
Enjoy your evening!