At start up, the controller starts the pump before the valves open, causing excess pressure in the pipes. At around 65 psi, the relief valve opens until the controller opens the valve for the first zone. Is this just a noisy annoyance or will it damage the pump over time?

I installed a pressure switch but that just caused the pump to cycle quickly until the valve opened. I'm trying to avoid installing a tank unless I absolutely have to.

I understand that the valves use pressure in the line to keep them closed (pretty neat, really) but is there some way I can reduce or eliminate the delay to open the first zone, and the delay between opening/closing successive zones? Thanks.