Do you not think Hell seems like a very extreme punishment, given the lack of available evidence for the existence of God? Why can't the non-believers simply cease to exist? Why must they be tormented in excruciating agony for all eternity? Again, does this sound like the actions of a loving God? This does not sound like love to me.
The existence of Hell is perfectly logical when we consider natural justice. Like our prisons on earth, there must be a place to go for those who live perpetually against the rule of law or in the case of Hell in persistent rejection of God. There has to be some place for evil people to go.
Even on earth we get a sense of the punishment deserved for evil acts. Acts, which can only take a moment to commit, which however are deserving of someone spending the rest of their lives in prison.
God, being infinitely just and merciful, offers every person the opportunity for repentance and forgiveness during their earthly life. However if someone freely chooses to reject God and persist in a state of mortal sin until death, they have separated themselves from God’s Grace and choose to remain in that state for eternity. The permanence of Hell is the result of human choices rather than a punishment arbitrarily imposed by God.
Most people aren’t saints, so it also makes sense that those not deserving of Hell (but also who are not saints) have somewhere to go. So in Gods mercy, this is where purgatory comes in. A place where people are purified to be capable of deserving of eternity in Heaven.
In terms of suffering on earth, here’s a good talk by John Lennox. He points out that Jesus Himself showed us the purpose of suffering from his own death.