Hey brother, not sure where you heard that test prop is "mild". Test prop contains the same drug as Test E or Cyp. The Prop is the ester, which determines how fast it is released into your body, once it has been injected. If you are injecting 700mg prop, in many ways, the effect would be very simiar as injecting 700mg Test Cyp or Sust or Test E. The speed at which it kicks in will be faster on prop than on longer esters and in the long run, levels will not build as high, due to the faster half life, but you will still be getting 700mg Test.
As for how long to wait between cycles? Lab work will show you if you have recovered. Rule of thumb is time on plus PCT should be equal to time off