I'm kind of hopelessly meticulous about brewing, but I think it has paid off for me. I have a split personality - really creative and easygoing, but also a big analytical/logical streak. So my life tends to be a battle for balance
After several years of making good beer, I'm working on refining my practices to consistently (and easily) make great beer. At the same time, I'm trying to really dial in my system where I know what efficiency to expect on a regular basis. I'm also brewing a whole slew of new beer styles, and doing my best to brew them to style the first time. Finally, working with water chemistry has added a whole ton of other "complications."
I live about 90 min from Minneapolis/St. Paul so I get down to the brew shop only 2-3 times per year. I plan my brewing schedule anywhere from 6 months to a year in advance, so I spend a lot of time studying and tweaking recipes to fit my efficiency, making lists, etc. Once I get all my ingredients and have the recipes planned, I enjoy making up the kits in advance so on brewday I can just grab the bag and go. I'm even thinking about packaging up brewing salts for each kit to really streamline my brewday.
I've done a few off the cuff brewdays and it was a nice change, but I've found that planning things in advance is kind of a fun lead-up to brewing. And having it all ready to go makes for an easy brewday.
That said, my ultimate goal is to have a set of solid recipes and repeatable brews nailed down to the point where things become predictable and automatic, and where I don't have to calculate things out every time.