i'm no expert but if you take the pinan series and open the hands, shorten the stances, spend all the time you're not doing kata in thinking of ways to damage the human body, you'll probably find out it's not made for little kids fighting in the schoolyard.
Also, for every "block" make sure you're aware of the simultaneous returning hand, then replace the word "block" with "strike" and "lever" also think of "clearing" and "ripping".
Another artifice is the separation of movement into little segments that give no hint of the possibilities inherent in three dimensional movement. In other words sideways, upwards, downwards, circular and straight can all be used to augment and harmonize with each other, creating something that is more than the sum of a sterile collection of "events".
It's just dancing, but so is fighting for survival.
About the stances, I practice low stances all the time. That's for the ability to react efficiently regardless of the situation you might find yourself in. Most classical kata do a pretty good job of recreating the archetypes of physical stress that one might be placed in. The same kata can be practiced legitimately many ways with emphasis on offensive, defensive, application and training. You can take an arm movement and lower the stance, then you've got the basis of a lever and throw, a lock or a neck crank. To make the throw effective, you might have to raise back to an upright position during the movement, or the other way around.
These patterns where made for a reason, and it wasn't for
The thing is, part of making a good pattern that is useful, or making use out of a pattern, is finding the difference between foundational and contextual movement.
It's really just moving meditation anyway.
Actually as you can tell, I am a expert on dancing around the room slowly with a serious expression on my face.