You don't have to turn a starship around if a crewman needs to visit Vulcan. You just give that Vulcan the necessary leave at an appropriate time, and he or she gets there by other means (which is probably quite easy, what with Vulcan being one of the most central worlds in the Federation). Spock was a very special case because he had no advance warning of his onset of pon farr.
Also, as said, most Vulcans might undergo their pon farr without much fuss most of the time. We met hapless singles in exotic predicaments, often undergoing pon farr completely out of schedule, so our viewpoint is quite biased.