The article is actually not particularly interesting. A person explaining what he himself doesn't understand seldom is. An atheist who looks in the Bible to find passages to disprove Christian ideas aren't very convincing to people who know what the Bible is.
Take, for instance, the two passages from Revelations. This book is pure apocalyptic literature, and anyone who takes it as being literal clearly has no understanding of Biblical literature. The book is highly symbolic in its use of numbers and images as well as coded language. And Austin Cline doesn't even know the tradition behind the scenes. He wrote, "Admittedly, these two passages seem to take place at the End..." Anyone who knows the merest iota about the war of Michael against the dragon knows that it is a story about a war before the creation of man, not something that will supposedly happen at the End. It is a tale from the deepest antiquity of Jewish tradition concerning the revolt of the fallen angels and the creation of the Abyss. How can someone point to evidence he doesn't understand?
"From the days of John the Baptist until now the kingdom of heaven has suffered violence..." This was during the days of the Zealots and the sectaries of Qumran who thought that they could gain admission to God's kingdom through holy war against the Roman invaders. To be honest, the word heaven doesn't properly belong in this verse, because it's not there in the Greek original. The Catholic version has "kingdom of God", and that is not the same thing. God's kingdom on Earth is not heaven, and Jesus was explaining that using violence to become a member of God's people was futile. Of course, Cline doesn't explain this because he doesn't understand it, and even if he did, it does nothing to support his argument.
"Truly I tell you, among those born of women no one has arisen greater than John the Baptist, yet the least in the kingdom of heaven is greater than he." Here is another example of a verse where the original has "kingdom of God". Its meaning is very obvious when taken in its proper context: the followers of Jesus on Earth benefit from Jesus's prophetic light, which surpasses that of John. John the Baptizer himself admitted that Jesus's station was above his own. Jesus's own teachings carried far more weight than John's words. There is no mention of a class system in heaven like Cline suggests, but why would we expect Cline to actually understand what he's reading? Understanding Scripture is never his purpose.
"Heaven and earth will pass away, but my words will not pass away." The Greek word ouranos means heaven, but more literally means sky. (Actually, the Greek text has plural hoi ouranoi, 'the heavens'.) Jesus is here using the literal meaning: the sky. He is not speaking of the afterlife abode of the Elect; he is saying that his words of truth are eternal, moreso than the temporary physicality of the sky and the Earth.
So Austin Cline falls short in his pointless refutation of that about which he
has no clue. Expecting to gain any insight about "the general impression among Christians that heaven is a great place to go" from this Bozo is like expecting the plumber to explain Spenser's imagery in The Faerie Queene. One must understand what he's seeing before he can point out its flaws; Cline doesn't.