Oh this is a nice topic
I am more like the person you are mistaken for Ryex, someone that doesn't have strict plans and just takes life as it comes. I don't do the planning ahead like you do, where you try to imagine and solve every possible scenario.
At any point in my life, I hold in my mind the large goals I have for my future. Right now, for example, they are to finish problem sets this week, get into grad school, get a job, etc. Once I have these goals in mind, I don't worry about how I will get there. I don't plan out when I will work on problem sets, or how many grad schools I will look into this weekend, or any of that. It's literally an on-off process. For example, at 7:30, I was just chilling, playing some starcraft, not worrying about a thing. At 8:00, I finish, check the time, and calmly begin working on a problem set. At 11:00, I finish, and go back to doing whatever I want. Since I don't have a rigid plan (or multiple plans like in Ryex's case), I can be interrupted, respond to surprises, and generally take anything that happens in stride.
So, to answer your particular questions,
1) The best way to live your life? Whatever makes you happy. I can say that my way always keeps me happy and at manageable levels of stress, so I think it's the best way for me. Maybe your way is the best way for you.
2) I don't see my own impulsive behavior as a bad thing. I still take the consequences of my decisions into account even when I make them on the spot, so even though I am impulsive I don't go around doing dangerous or irresponsible things. In my opinion, my impulsiveness represents my freedom from the basic network on which society is organized. I've often heard people say they don't have the time or the ability to do something, whether it's something insignificant like intramural soccer, or something important like following their dream of becoming a choir director. I attribute this to rigid planning, and their inability to come up with a creative way to accomplish a goal. In other words, I think my impulsiveness frees me from society's limits, and gives me the power to do whatever I truly want to do.