In your OP, you mentioned battery life specifically. Battery life will vary according to individual usage. Speed will vary by phone and how the phone is used. Some DXs are very quick, some lag horribly. It really does depend on the individual phone. Re-reading your post, yes, you could possibly have a chart that says what components of a rom are Blur or AOSP... but even that can change from update to update. You're just not going to get a completely comprehensive comparison. If there are a couple specific roms you're looking at, maybe post a thread with your questions and get user feedback?
My husband and I both have DXs. We have always ran the same roms. He's not into the whole modding thing, so once I find something I like more, I update him to the new rom. And our phones, purchased the same day, running the same rom, with similar apps and widgets, in the same corner of the world, will react very differently sometimes. People have different experiences, even with the same phone.
