I was wondering about that. Would the following strategy work?
1) Wipe as needed and then flash a new ROM.
2) Use Titanium Backup to restore the apps and data you want restored.
3) When the new ROM is all fixed up how you like it, make a nandroid backup of it.
4) Repeat step 1-3 with a different new ROM.
5) When or if you decide to start using one of the previously tried ROMs again, instead of repeating steps 1-3, simply restore the nandroid backup of that ROM.
Wouldn't that work? Wouldn't the nandroid backup restore the custom ROM complete with all the apps and data you restored to it?
Thanks.