Here is something that really helped me when I rooted -->
Howto: Root the HTC Droid Incredible - Technology - Jonamerica.com I know most of it is old news, but it is still good information.
I don't know why you would need to remove your SD card, no real concern there to my knowledge. Do a Nandroid backup. Power off your phone, then hold down the down volume button and the power button at the same time. You will be in bootloader, After it does it's thing, looking for a PB13.zip file, you need to use the volume button to go down to recovery then hit the power button. You will be taken into recovery. With the volume buttons, scroll down to Restore and Back Up. Press the track pad to select it. Scroll down to Back up and press the track pad button again. Once you have done that it will begin backing up. Put your phone down for about 5 minutes. It will come back to the previous menu when it is done. Press the track pad on Reboot the device. It will reboot. Once it downloads go
http://androidforums.com/incredible...root-guide-updated-4-15-est-oct-1-2010-a.html and follow the directions.
Titanium Back up after root prior to flashing any rom and it will restore your apps for you. If you buy it, you won't have to press the install button for each app as they reinstall.
If you do not wipe data between Rom changes, you won't have to reinstall anything. Some apps need a wipe to work without bugs, some don't. If and when you do a wipe and you are reinstalling apps through Titanium Backup, uncheck any red apps, it will keep conflicts out of the new ROM.
Make sure you have your contacts synced in Gmail.
Other than that, I can't think of anything else that you need to back up.