But the slowest period I can get (I think) is 70Hz. (Postscale=16, Prescale = 16, PR2 = 11111111) and a servo expects pulses every 20ms (50Hz).
It doesn't have to be 20ms, thats just the Admin recommended wait. I sometimes go as low as 10ms, but I've found some servos start to overheat at that rate . . .
I want to use the CCP peripheral so that I don't need to use delay functions in my program and waste processortime... Is this a good idea?
Well, using the delay method, each servo will cause a delay on average 1.5ms. So 5 servos would cause a delay of about 7.5ms. If you send a command to a servo 10 times per second, thats 75ms, or about 7.5% of total processing time. Unless you are doing some crazy processing, thats fairly insignificant.
Your PIC probably has only 2-4 PWM channels, meaning it won't really save you any processing.
The one advantage however is that with PWM it becomes a 'set and forget about it' command. You wouldn't need to worry about sending servo commands all the time. You could also use timer interrupts to run servos as a set and forget function, too.