Here's my input on a few things:
First - contacts and apps and stuff, yo. USE A GOOGLE/GMAIL account! I had a GMail account long before Android came out, so it was natural to just use it. Contacts and apps are somewhat backed up that way. At least the contacts are fully synced over the air automatically. When you load up a new ROM or do a factory reset of your device, you are asked to sign in to your Google account, then it asks if you want to use it to back up your data. I can't remember exactly what it says, but it is something to that affect. Then when you switch to another ROM and sign into your Google account, it doesn't really restore everything exactly as you had it, but it does reinstall the applications you had installed. At least mostly. I've noticed a couple things missing, but most of my apps get restored.
Again, while the apps get restored, the data and settings do not. I haven't really messed around with Ti Backup to try to restore app data/settings yet.
As far as connecting to the ARFCOM mail server, I don't know what the settings are because I don't use it. I would guess it's a simple POP3 setup, but it may actually use IMAP. You'd have to dig around and see if there's a Silver/Gold member FAQ. The settings should be the same on your phone as if you were setting up a client on your desktop computer... so I'd assume that information is out there on ARFCOM somewhere.