Rotating is a good idea if you have several layers, a full humidor or cigars with large differences in profile (Gurkha Black Dragon next to Macanudo). This will minimize flavor marrying.
If you smoke through them quickly I would not be concerned with rotating.
I dumped my 2 small humidors and picked up a chest good for 300 sticks. The top tray reads 65% and bottom is running 73% consistantly.
I've got it loaded with about 200 cigars and thought rotating them might be a good idea to even things out over the long haul.
I used to until I got around 2500 cigars and then it became a big hassle. With proper ventilation and air flow in the humi I never needed to rotate them.