[edit: After posting, I noticed you said you basically want a hard, external martial art. however, my recommendation could still be of some interest later on]
The martial art that I love the most and I could never get bored of, is Tai Chi. It is not just a combat system, it is also an internal practice and a meditation in movement. It makes you feel more energized, more focussed, you feel your body more "in one piece", as you develop a stronger body structure, better posture, and deeper breathing. However, the power you gain is internal, not external. You will not get physical strength, speed or anything of the sort. However, you will increase your internal strength (as you see Master Wong below), and you will be able to throw people through the air if you will want to. This however should never be the focus, if you are to take up Tai Chi. Also, training should not be hard, not even 101%, not 200% as you say. Tai Chi is all about conserving internal power and gaining more and more, and not wasting it though exercise. It is about building your body, energy, and ultimately your mental and spiritual power, and not about expanding it outwards (except when you actually need to defend yourself).
YouTube - Tai Chi 24-form
and as for combat applications,
YouTube - Tai Chi Combat 1 video Preview