Which martial art to choose?

Okinawan Karate would be best for you. It is strike driven yet has grappling in the stand up. Pressure point attacking from the stand point of the Human muscle anatomy and skeletal system as well. Okinawan Karate would be prime for a person such as your self seeking a art that focuses on quickness and balance. It is a art that is not commonly practiced per say anywhere and everywhere, but it has plenty of practitioner's none the less. It is a good art to study, but I'm not saying that any art isn't a good art to study, just saying it sounds like it's more of what you're looking for. It even puzzles me why more Okinawan Karate teachers don't have their students fighting in amateur cage matches nation wide and I mean that in all sincerity. Okinawan Karate practicioners would be way more effective than Chuck Liddell's Kempo Karate ever thought of being in the cage and that's no lie.