In my case, my settings came from a mix of trial and error, moving some coral around a bit, and personal taste. I've never used a par meter, but I'm sure it would have helped, and might still. I just enjoy playing around with things, although in this hobby, I've had to restrain myself to make small changes and wait for a while.
I'm on the road for 8 days, then home for 6, wash, rinse, repeat. The tank usually looks better after I've been away not messing with it.