If you register all your instances in your Enterprise Manager tool, then monitoring is less of a pain, because all you have to do is open up each instance name and refresh the jobs every once in a while so you can see if they're running. With everything registered in one tool, it's easy to look at.
The main thing I keep forgetting is that just because I can see the instances, doesn't mean I can restore them or back them up to my local hard drive. I keep trying to do a restore, catching myself because I don't see my drive setup, then playing musical chairs with the backup files to move them to the proper instance I'm doing my restore to.
Lastly, make sure you have a test server, and not a test instance, set up for testing restores, etc. It needs to be a separate physical machine, even if you register it in your own version of EM. And Remote Desktop is a wonderful tool for when you have to log into those remote servers and check Event Logs, etc.
Catadmin - MCDBA, MCSA
"Just because I'm paranoid doesn't mean the universe *isn't* out to get me!"