I've heard people question why the Savior had to die. They reason that if God has all power, then he could just bring us back into His presence.
Envision that happening. Can you see yourself happily being in God's presence as you are now? I can't. A prophet in The Book of Mormon explains what would really happen to us:
"the demands of divine justice do awaken his immortal soul to a lively sense of his own guilt, which doth cause him to shrink from the presence of the Lord" Mosiah 2:38
I've heard of a mall that was having trouble with gangs frightening away their customers. They asked a professional for help. His solution -- play classical music. It worked! Why? Evil is not comfortable around what is beautiful and good. Knowing this, we fill our streets with light, because we know that violence and crime thrive in darkness.