Nicely said, Scroggs.
All a landing clearance means is that within the bounds of that country's rules there is no known impediment to you using the runway to land.
In other words, as long as *you* are satisfied it is safe, the tower controller should have met all that country's rules to allow you to use the runway to land. It is *always* your final responsibility to decide if a landing is the best course of action.
Doesn't matter if there's no aircraft ahead of you (landing *or* taking off) or if there's one lining up, nothing at all or 5 aircraft ahead of you. The ultimate responsibility lies with the PIC to decide if landing is the correct action.