Dante's Inferno and God's role

Being raised Catholic I grew up learning that hell is simply where bad people go. But I never imagined its structure or the horrors Dante describes in Inferno. The first circle of hell, Limbo, I found particularly disconcerting: "...they did not sin; and yet, though they have merits, that's not enough because they lacked baptism." (Canto IV 34-35) The idea that simply not believing in God, regardless of how well you behaved on Earth, results in indefinite confinement to Hell is terrible. Some of the people in Limbo I would guess could have never even had exposure to Christianity before their deaths and thus not believing in God would not necessarily be their fault yet they still must suffer. Simply put, ignorance to Christianity sends you to Hell and not committing to Christianity through baptism sends you to Hell(136).
I also found it disturbingly interesting that Dante believes that even having one sin that you never confessed to God and prayed for will send you to Hell. Even the most virtuous people on Earth end up in Hell for a single sin maybe as petty as being lustful or practicing astrology and to me this seems to go against the very idea of Christianity. It seems weird that Dante would describe his perfect, righteous God as one who would punish his best acting servants for one sin they may have committed in a heat of passion or been unable to control. When I used to think about God I always imagined him as a kind, forgiving, benevolent presence that preferred to see the good rather than the bad in his children, not as a harsh, condemning presence looking for reasons to send his people to Hell and suffer indefinitely for one act of "unfaithfulness." (155)
Ultimately I believe Dante has some serious religious issues and in writing this was merely looking for ways to scorn his enemies since I have a hard time believing that the kind, forgiving God would ever work in a way so condemning in nature.