Re: If the Moon were replaced by other planets...
Some of it might be down to perspective. Sometimes bodies such as the Sun and the Moon can appear larger or smaller than they actually are depedning on what else you are looking at.
Remember the Sun is something like 400x the diameter of the moon, they only look the same size because the sun is 400x further away from the Earth thn the moon.
On the continent of wild endeavour in the mountains of solace and solitude there stood the citadel of the time lords, the oldest and most mighty race in the universe looking down on the galaxies below sworn never to interfere only to watch.