Marine propulsion control system and method with collision avoidance override

A marine propulsion control system includes at least one propulsion device, an input device enabling user control input commanding movement direction and velocity, and at least one proximity sensor configured to generate proximity measurements describing a proximity of surrounding objects. A controller is configured to first limit the velocity commandable by the user via the input device based on the proximity measurements so as to maintain the marine vessel at least a buffer distance from any of the objects, then receive a user-generated instruction to suspend maintenance of the buffer distance in at least one direction and a user control input via the input device to move the marine vessel in the at least one direction and toward a first object. The at least one propulsion device is then controlled based on the user control input such that the marine vessel approaches and impacts the first object.