OP:
Here's just a quick reference (in my opinion)
CM6 - Will be the fastest of any custom rom, especially if you continue and install a snap kernel.
BUT - No 4g, HDMI, FM Radio as mentioned. Also you will lose Sense, and may have many issues arise when trying to use features of the phone. For instance, Wireless Tethering can give problems. CM6 is a GREAT rom, but I would say it's the most high maintenance as there will likely always be something going on strange that needs to be handled or corrected.
Fresh 3.2.0.2 - Great Rom. It's got a lot of the additional Sprint bloatware removed. I used Fresh as my primary rom for quite some time, on the Evo and my Hero.
BUT - I can tell you it won't be the snappiest rom, and there's really not much customization going on. It's a great rom if you just want to drop some bloatware and run a custom rom, very little maintenance ever required.
Caulk's Evio series 1.2 - This is a great rom as well. Has most the bloatware still in place, but the battery life won't suffer and you can actually remove sense and the bloatware through ADB with this rom. Everything works as it should after installing the update patches included with the Rom thread.
My history is Fresh (3 months) CM6 (1.5 months) Evio (2 weeks). I have to say I miss the barebones feel and performance of CM6, but no 4g turned out to be a dissappoinment (though I rarely even use it) and I also had lots of problems with tethering no matter how much I messed with it.
I like Evio and plan to stick with it for a while. Everything just works, the phone is still performing very well and I didn't have to make any sacrifices.
Now, You make the decision.
****And I don't want to hear anyone bashing back at me about my opinions... I offered them to answer the OP, not for your personal judgement****