I pretty much agree with stepfam. (Actually, I pretty much agree with stepfam all the time.)

1. I'd try some 1 1/2" slick tires. Run 'em up to about 80psi. Tires narrower than 1 1/2" may fit but they start to look a little goofy.

2. Think about any accessories that you have on your bike and all of the junk that you carry with you. I'm not saying that you should ditch the kickstand, but you need to justify every single item in your own mind.

3. Your fork and suspension seatpost will have preload adjustments. I'd gradually snug up those adjustments. All of the bobbing up and down that you do not only lowers your efficiency and the amount of power that you are putting out, but it also consumes some of your power needlessly.

4. Everybody worries about smooth shifting but you only shift less than 1% of the time that you are on the bike. Your fit and position on the bike affects your comfort, efficiency and performance every single minute that you ride so it's much more important. Don't be afraid to experiment with saddle and handlebar position until you find the "sweet spot".