Understood. I keep my eyes on the target so I usually didn't overshoot and when I did I had forgot the option to stop in midair violating physics law =p
What physics law! You can pull up enemies into the air without dropping down yourself, anti grav man. I use X and , ground pound to stop. Land in style. It's something you have to unlock first though.
I'm getting the hang of the challenges now, however the bomb ones are still hard. Drones as well. I can't get the timing right for the R2+L2 + X launch. With all the gadgets maxed out (except the last 2) combat and stealth become pretty easy. Trip mines and impact web clean up fast. I need to progress the story a bit first now, bored of being stuck in the night.