If there are multiple report suites that are set-up the same way, you shoul dbe able to use the Admin Console to set the default metrics for multiple report suites at one time. Currently you can only do this for one report suite at a time (lame!)...
just ran into it this again and made some poor ClientCare guy very unhappy by having to update the default metrics for my 4,000+ report suites
I absolutely agree w/ Adam.