Currently, I have 4 handguns in the "rotation". I don't really rotate carry guns per se, just have different models for different purposes.
Primary: Russian Makarov. Easy to shoot, tough as nails, and 100% reliable.
Backup: Iver Johnson Cadet 55-S in 22LR. Small, cheap and it works.
Outdoors/Winter: Colt King Cobra, plenty of punch for most jobs.
Breaking In: Kel-Tec PF9, small & light. Once it has proven itself it will be my EDC.
I used to CC a Colt SAA .357 on a regular basis, but I have semi retired this one, it only comes out on range days. When I am out and about in the great outdoors, I generally open carry a .44 Mag or one of the .357's.
So depending on what's happening on any given day, I could be carrying a hammer fired DA/SA, a striker fired DAO, a DA revolver with a swing out cylinder, or a DA revolver that loads single action style!