Not sure if this is the correct location for this thread, but here goes.
I have a 2006 Trek Fuel 80 that I currently ride and enjoy. I am to a point now where I would like to get better quality parts and decrease the bikes weight. My main concern is whether or not the Fuel 80 is worth building up. The other option I am leaning towards is buying a new bike setup the way I would like. Finances are tight right now on a single income though. I have probably 2-3K to spend. Other bikes I am looking at are hardtail 29ers such as Air9 Carbon, Orbea Alma, and GF SuperFly. Let me know your thoughts.

Also,
I ride mostly technical trails in Colorado with lots of climbs.

Thanks,