I think you should learn to put up with it, and I say that because you can get much better battery life by modifying your habits just a little bit. I get about 8-10 hours of battery life with moderate use, and to do that I leave WiFi, 4G, and BlueTooth off when I'm not using them. Sure, in a perfect world you'd leave everything on all the time, but the Evo has a lot of power crammed into it and so that just means we have to compensate for that a bit. I also changed the syncing options so that my accounts sync less frequently. It's worth noting that there is a bug in the flickr sync that causes the calendar app to prevent the phone from sleeping. Unfortunately, until this is fixed it's best just to disable your flickr account on the phone.
I leave my phone plugged in overnight, and I also plug in into USB whenever I'm sitting at the computer so that it charges some more. I'd recommend purchasing a car charger to charge it when you're driving, or perhaps purchasing a spare battery (an option that doesn't exist with the iPhone). Seidio makes a battery with slightly more capacity than the one that comes with the Evo, and it is still the same size as the normal battery so it doesn't add any bulk.
MobileCrunch's review of the Evo compared it to a Ferrari. I think that's a great comparison seeing as how Ferraris get about 10-15 mpg. I think it's worth "filling her up" more often in exchange for all of Evo's great features, but ultimately you need to decide for yourself if you can learn to put up with it.