Nightwing is proven to be a far better natural athleate as well as a better acrobat than anyone else(non-meta) in the DCU. He did not learn everything from Batman, however he did learn most of his skills from Bruce. He did in the process teach Bruce a thing or two. Dick never used a signal during the time he was in the 'haven, as he wanted to move away from being fully associated with Batman. That was part of the reason why he became a police officer during the daytime, so he could have better access to what was going on with the city's crime. I would not say that Nightwing is a better character than Batman, just diffrent(and equally as good).
Keep in mind about Nightwing's origins. He does more of those flips and such because he and his parents performed high wire acts in the circus. With these skills, combined with the kind of training Nightwing got from Batman when he donned the identity of Robin, makes this guy a strong force to reckon with.
Is he cooler than Batman? I guess that's always up for debate, but I find Nightwing to be in a league all his own. In some way I find that character to pose as another version of Batman, but merely in a different costume with a different personality.
Did that make sense there? lol
Richard Ward was raised by Bruce Wayne shortly after the death of his own parents. It comes as no surprise that his own lifestyle would both mirror and contradict that of his former guardian. Like most sons, whether the relation is by blood or not, they always want to carve their own path for the sake of claiming their own identity. This is how I see Nightwing.
There are so many possibilities with Nightwing that it's ridiculous.