To reduce wear/easier maintenance/less costs, I started to ride a singlespeed 52/16, now about 7 years ago. 2.5 years ago, I also digged the remaining tech, the freewheel, because in winter it frooze and in heavy rain the springs suddenly failed to return the sticky pawls. (=end of riding, freewheel in both directions).
Since, I ride a fixed gear, with an 'empty' (default luggage) weight of 25 kg. The 3 drive train components 1/8", extra heavy chain (550 grammes), extra thick sprocket teeth. I'm now riding 8 months, 15000 km with the same drivetrain components, and as it looks like, a whole year without replacement should be doable. The years with 4 chain, 2 rear cassettes, 1 chainring replacements, are long gone.
Braking, that's just pushing back.
Balancing, much easier, since you have support on both pedals instead of just the front spinning one.
Only drawback: don't turn sharp corners, a pedal may strike the ground and you're thrown somewhere you didn't intend to be.