Another thing, "regular maintenance"...
"Regular" maintenance does not have the same connotation in OS X as it does in Windows.
After 15 (now getting closer to 25) yrs using Windows, and as a semi-extreme gamer and overclocker at the time I bought my first Mac - my regular maintenance had been once a week. Like most of you, I tried carrying a lot of those habits over from that experience and it took me well over a year to figure out all that stuff really was not required to maintain the speed of OS X.
Unlike that other OS, regular maintenance on my Macs now occurs, typically, only "after" I notice slow downs, not before.
How often you'll need to do any type of maintenance depends on your usage patterns. For me, that's about once every 3-4 months if using a hard drive. My wife hands me her machine saying it seems to have slowed down once every 9-12 months. I believe with my first SSD, I did nothing that would be considered "maintenance" until it was well over a year old.