I want the fresh install, but also want to keep all of my text messages. The rest of the customizations, I'll take the time to put back myself (I do this all of the time, and usually manage to find new ways that I prefer it optimized).
I believe I can update to iOS5, do a backup, save my text messages, freshly reinstall iOS5 (once a jailbreak is available), and then use something like iFile to restore the text messages to the phone. Hopefully it won't be a huge issue.
Edit: clarified the process