Seat height
Your seat height should not be determined by it's relationship to handlebar height. You could be setting yourself up for knee problems. Your seat height should be such that your legs are almost fully extended at the bottom of your pedal stroke. To get a more aggressive riding position go for a negative rise stem. I recommend consulting your LBS for these adjustments so youdon't compromise overall fit and comfort.
"Only those who dare to fail greatly can ever achieve greatly" (Robert F. Kennedy)