this is a very short one
The ability to fly was Danny's favorite power, being near the stars whenever he wanted was a dream come true and the fast way to travel in his daily life was a plus. It wasn't until some months after getting his powers that Danny started to think of what exactly was his ghostly flight and his conclusion made him like it even more.
This power didn't just let him float and move fast in the air, it let him ignore gravity in himself, it explained how his floating was somehow like standing in air or how he could walk up walls like it was the floor.
Danny discovered he couldn't share this power as easily as his intangibility or invisibility, or as long. Even with that limit he still gave his friends pleasure flights around the town, he also used it to hide from bullies or adults by walking to the ceiling, after all most people don't look up when looking for a human boy.