I spent some time optimizing the battery life before I rooted (in June). Back then, it was pretty much just googling battery saving tips for the evo and trying them all. I was able to get my battery drain down to about 2% an hour with the screen off (overnight loss of about 15-20%). Connecting to my home wifi instead of using 3G was a big help.
Then I rooted (July). With setCPU, I got the overnight drain to about 5-10%. Then Froyo came out and shit hit the fan. After I upgraded, my battery life was horrendous (drains in less than a waking day). After rechecking all my settings and apps, I finally caved and did a hard reset. Then I manually installed all my apps and manually set all my settings. That did the trick. battery life was back to 5-10% drain overnight.
Then the HAVS kernels came out. HAVS significantly improved the battery life of the phone while it was in use. So with HAVS covering usage, and setCPU covering screen-off, battery life has been very good.
A few things to note: playing mp3s from your SD card takes almost no battery at all. Pandora is totally different, since it requires the music to be streamed, which means radio use, which drains battery.
Wifi saves a lot more battery than cell tower signals. If you have wifi at home, make sure your phone auto-switches to it when you're in range.
The only things I have syncing automatically are my exchange inbox, gmail inbox, and a weather widget.
I have an app called System Panel (I have the paid version) that shows me the history of CPU and battery usage. It gives me a list of which apps used the most CPU in a given timeframe. It also shows me the real-time CPU usage of apps (standard in the free version as well). I know there's a lot of battery management apps out there, but I think System Panel is by far the best.