just rooted my incredible the other day - got the wifi tether to work (then found out there is a way to get the 2.2 3g hotspot to work without root.) disable some preloaded apps. still researching how to get custom roms and stuff
my incredible is rooted and I'm running the cyanogen mod. its really easy to flash a new rom. just download the rom manager, go in and download new roms and bam there you go. they always ask you if you want to backup and wipe, you always backup and wipe. if there is an issue you reboot into recovery and backup to where you last left off and you are all good.
if you are going to run cyanogen mod stick with 6.0.1, the 6.0.2 version has an issue with the email and an error keeps popping up. I've been running 6.0.1 for a few months and its been running great.