What Type of Martial arts is best for me?

You definitely cannot have one particular style satisfy all the things you are looking for. Using one's strength against them is quite far away from being swift, striking and steady. I'm tempted to suggest Tai Chi to you, for the strength against oneself part but its pretty darn hard to find a self defense Tai Chi master. The second thing which came to my mind when you mentioned using an opponents strength against himself is Aikido, which is full of controlling energy, manipulating an opponent's movements and throwing them. Judo would also fall into that category as many of its throws depend on how hard an opponent charges at you or resists you. For your legs a kickboxing martial art would do the trick, Savate, Kickboxing and Muay Thai are just some examples.