I'm a landscape photographer so my custom settings might help (on a Mk3 but should be compatible)
C1 is my main go-to landscape setting which gives me a quick starting point.
ISO100
Manual exposure
F11
1/30th
Mirror lockup
Single shot drive
Single point focus, though I usually manual focus or use liveview
C2 is my long exposure setting, for Big Stopper shots
ISO100
Manual exposure
F11
bulb
Mirror lockup
Single shot drive
Single point focus, though I usually manual focus or use liveview
C3 is my bracketing setting, for HDR
C1 is my main go-to landscape setting which gives me a quick starting point.
ISO100
Manual exposure
F11
1/30th
Mirror lockup
Motor drive
5 Shot bracket, +/- 2.5 stops
Single point focus, though I usually manual focus or use liveview
I hasten to add I use these as a quick base setting, I vary them as required, it is just handy to know that if I see something as I'm driving that I need to grab then C1 and I'm up and running in the right direction.