"Rotation" implies equal time and equal intervals. I do not use a rotation system. That being said, unless I am in the shower or in bed, I have an SP101 on my person. If leaving the house, in normal street clothes, I normally add another SP101, or an S&W Model 19, or, sometimes, a Les Baer Thunder Ranch Special 1911. Yes, 2+ guns is normal.
If going to work, which is not normal street clothes, the SP101 is concealed, and a P229R DAK .40 rides in he duty rig, openly. A .357 sixgun goes along off-body, as does a Remington 870P. (I own my duty weapons, which is normal for this region.)
I generally like to keep things simple, which means not mixing weapon systems with varying manual safety devices and varying trigger systems. When I was carrying 1911 pistols, it was 1911 24/7. When I carried a DA/SA P220, it was my 24/7 gun for two years. Presently, my carry and duty handguns are all long-stroke DA, excpet, obviously, my 1911. As I get older, and weaker, I have started looking for good geezer guns. I pulled my 1911 out of the safe, and found it recoiled much more gently than my snappy SIG .40, which has been torturing my bad wrist. Another thing I discovered is that I can indeed mix the single-action-only 1911 and long-stroke DA successfully. The distinctive checkering and shape of the 1911 grip instantly tell my hand what it is grasping, and my old 1911 training comes right back to me.
I have had problems, however, in the past, mixing Glocks and SIGs; a session with a Glock could actually cause degraded performance (trigger control) when I would then shoot a SIG DAK. So, I still advocate that folks be very careful about carrying or "rotating" differing