Any thoughts to adding disc brakes to your bike? Especially if you plan on racing. Of course that also means upgrades to disc ready wheels etc. I would just stick with something like Crossland wheels and Avid Mechanicals.

Also I would consider a riser handlebar. Don't know inches - usually they are measured in cm's. Also consider a riser bar.

Tires - for racing - Continental, Panaracer and Kenda make fast, reliable tires. Do some research on their websites.

I just got done added some "bling" to my HT - I upgraded to full XT, added a King Headset plus Hope seat post clamps and skewers, added Crossland wheels (off an old bike) and Avid mechanical disc brakes, a Thompson seat post, a riser handlbar and am good to go. The bike now rides beautifully!