Welcome to the site, Ian.
Difficult to define "quite heavy", as what is preceived as heavy (or light) by one may not be by another. Said, I would define the steering effort of my 2004 MY 2400SC3 as fairly light, needing nothing more than a single hand or a stiff finger. Heavy steering could be attributed to several things; power steering pump is weak or low on fluid, a slipping drive belt, the cable from the helm to the steering linkage is worn, needs lubrication, or is binding, or the steering linkage itself needs service. As to the free play, again, could be several things but understand that the steering systems in boats just are not as accurate and tight as those in cars. Nevertheless, inspect the steering system from helm to drive; have someone move the wheel left and right a little and look for play. The drive should move almost as quickly as the wheel does.
Have you had a mechanic inspect the boat?