Your kung fu style should provide all of the above.
However, I would make this list based on my personal experiences and current level of skill:
1.) Technique. Spend more time on this than on anything else…this can include structure, position, all movements specific to the MA.
2.) Heart or spirit. You have to be willing, and very able to put yourself on the line and be humble through daily training and exploration. You have to be able to push through the pain, the humbling experiences, and keep striving to become a better martial artist. This can also refer to having a calm, collected, and clear mind that is aware…basically any attribute not physical that one can cultivate can be labeled as heart or spirit.
3.) Conditioning. In this I would include your cardio-vascular system and your ability to take and give a hit. If you can’t last a minute of sparring at an intense pace, or get winded from one hit and are unable to proceed, this can be bad.
4.) Power. Through technique and supplemental exercise, you develop the power to strike hard and to utilize the technique when encountering applied force. I would include strength in here as martial arts is more about explosive power than raw strength.
5.) Balance. This means both physical balance, coordination, agility, and speed, but also mental and daily life balance. The yin yang mentality and image of a well trained, not over trained or under trained, and yet relaxed and calm person.
Those are the current things I consider when training and where the value is. However, I train some areas much more or than others because of their underdevelopment so that this does not refer to a developmental path from 1 through 5 but rather the value as I see it in these five areas.