Power comes from proper body mechanics and knowing how to strike, while speed comes from the footwork and from the experience of knowing 'what comes next', because you've been there before. For reflexes, defensive or offensive, you pretty much have to train the drills with another person so that you learn the timing, and also for the 'realism' mentality, which is a lot harder when you're practicing solo. The most you can do to improve those first three (once you have the basics down, of course) is to just keep practicing - they increase over time.
As for accuracy - I have a suggestion:
So, you take a piece of tape and you stick it on a wall at eye level. Then you take one stick and orient yourself so that your weapon side is closest to the wall, and so that when you strike, you can avoid hitting the wall with your stick. Now, from chamber position - [your arm against your body and your stick resting on your shoulder on the same side] - you practice making your strike: flip the stick out horizontally until it just lines up with the tape, (try not to strike past your target), and then let it come back to the chamber position. From there, it's just a matter of repetition.
It's a simple drill but it's very effective, *if* you practice with the right mentality. each time you strike you have to focus on aiming at the piece of tape - that way, with every strike, you're teaching your body to hit exactly where you're aiming. on the other hand, if you zone out and do the physical part of the practice but you don't hook it up to the mental part, you're only teaching your body that one strike, so your overall accuracy doesn't benefit.
(My kali instructor told us about this one time) :asian: