The amount of heat from radioactive materials is also proportional to the mass of the planet. The more diverse the surface geography of a planet, the more involved is the tectonic activity. For example, the Earth is one of the most tectonically active planets in the Solar System and has extensive systems of plate boundarys, active volcanos, mountain ranges and canyons. The fact that the volcanos on Mars are large implies that Mars was once active, in its distant past but with limited plate motion . Depending on the mass of the atmosphere, this list is in order of strength.
Atmospheric erosion has short timescales, on order of hundreds of thousands of years.
Tectonic activity can take on order of millions of years. Gravity slumping is only visible on airless worlds with timescales of billions of years. Note that large features, such as impact basins or extremely large impact craters can not be eroded away even after 100's of millions of years. Such large features on the Earth were eroded by tectonic activity, i.e. the crust was recycled by plate motion such that those ancient impact basins are gone. Old surfaces are heavily cratered.