Righty then…
“Will God save everyone?” – Yes, or at least God will keep at saving everyone forever (even if there’s a stalemate.) But I find the scriptures to reveal He will eventually save everyone from sin. Not necessarily from hell.
“Does everyone go to heaven no matter how bad they were and no matter what they believed?” – Do the elect go to heaven no matter how bad they were and no matter what they believed? Will they be saved by Christ without having to earn their salvation, and be led by Christ to live and believe better? Would a God Who loves and saves sinners, bringing them to light and to life, still be holy and just? If so (and Arms and Calvs both believe so, but especially Calvs!), then why would the principle be different if God saves even those He has not elected to be Christians in this life? These two questions do not address the real issue, unless the real issue is supposed to be a complaint that God would save any sinner at all!
“Is Hitler there next to Bonhoeffer enjoying the same eternal bliss?” – My guess would be not yet. But eventually yes.
“What kind of God would that be?” – A God Who graciously saves sinners and brings about peace and righteousness (fair-togetherness) and joy even between the worst enemies, so that grace is hyper-victorious over sin. (Instead of sin being hyper-victorious over grace.)
“Would that God [Who saves Hitler the sinner as well as Bonhoeffer the sinner and makes peace between them] still be holy and just?” – Absolutely. Or else the same complaint could be made in principle against any reconciliation of enemies under God. Which no Christian anywhere has ever complained about. Would that God Who saves Saul of Tarsus, who murdered the church of God, as well as Stephen the martyr, whose death by stoning Saul heartily approved, still be holy and just? Would that God Who saves Simon Bar Jonah, who was once called Satan by Christ for opposing Christ, and even cursed himself rather than keep his promise of loyalty to Christ, as well as Kevin DeYoung the good and (no doubt) sinless Christian teacher who, unlike the chief of Apostles, so impressed God that he earned his own salvation from God, still be holy and just?
“How would we make sense of Jesus’ strong language about hell or the chilling scenes in Revelation?” – By believing in the strong language of Jesus’ hope (“All sins and blasphemies no matter how great shall be forgiven”) as qualifying the strong language of Jesus’ warning (“Blasphemy against the Holy Spirit shall not be forgiven in this age or the age to come”), instead of believing in hopelessness over hope. By believing in love even in wrath, rather than in graceless wrath over grace. By noticing that the chilling scenes in Revelation are offset by revelations of what will finally happen after Christ shepherds with the rod of iron (as an enactment of the Hebrew of Psalm 23!): the Son and the Spirit lead the kings of the earth and their followers out from the lake of fire, and out from the number and the idolatry of the beast, into the New Jerusalem, both with and without the help of the Bride of Christ. By believing in the fair-togetherness of the Trinity as the ground of all reality, rather than the monomaniacal pride of mere monotheism. By believing in the cross as the heavenly throne on which Christ reigns (as RevJohn reveals), and in the blood of the cross by which the fullness of God is not only delighted to dwell but to reconcile all sinners to Himself whether those in the heavens or those in the earth.
“And what would that do to our understanding of the gospel?” – Well, for one thing we would believe in the “eonian gospel” proclaimed by the angel in the heavens in RevJohn, instead of denying and rejecting that the gospel is “eonian”. A Calvinist ought to have advantages on this topic over an Arminian!
“Would Jesus’ death still be necessary?” – As necessary as it was to save any sinner, whether in the heavens or on the earth, through the blood of the cross.
“Would faith in him really be that important?” – As important as the faith of any person led to faith by Christ. (Again, a Calvinist ought to have advantages on this topic over an Arminian!)
“Why would we still send out missionaries and evangelists?” – For the same exact reasons Calvinists send out missionaries and evangelists to preach to those of the elect among the non-elect; God’s ultimately sovereign and sufficiently effective choice to save the elect (later if not sooner) does not negate evangelism, so Calvinists believe. Why would God’s ultimately sovereign and sufficiently effective choice to save sinners (later if not sooner) negate evangelism if the scope of real evangelism is Arminian instead of only Calvinistic?
“What would be so good about the good news if, in the end, there is no bad news?” – What would be so great about God’s victory if God’s victory was complete? But Calvinists, like Universalists, actually do believe (unlike some Arminians) in the complete victory of God. So is the Calvinistic question rather, what would be so great about news of God’s good victory if there was no bad victory of God? (But then Universalists and Arminians are derided for suggesting that the Calvinists preach a gospel of utterly hopeless bad news for some people, which is the very anti-thesis of good news, instead of a gospel of hope for all people.)
“And if there is no hell, or we can’t really be sure anyone is there, why have almost all Christians in all of history believed there was such a place of eternal suffering?” – Do sinners tend to believe in hopelessness from salvation, and/or in hope for the continuing of their sin? Would people who believe this not tend to interpret scripture (and try to reason principly) along this line? Are any Christians in all of history not recovering sinners?
“Have we found something that historic orthodoxy has missed all these centuries?” – Historic orthodoxy in the East didn’t miss this for all these centuries (although neither do they dogmatically affirm universal salvation.)
“What if the things you’ve heard recently are not the truth about Christianity?” – Then Christianity is about hopelessness of salvation from sin. Maybe about hope of salvation from sin, too, but maybe not for ‘you’ over there, who knows?
“What if the warnings in Scripture are real warnings?” – Then they are real warnings about hopeful punishment. Not hopeless punishment.
“What if God is purer than we thought, we’re worse than we imagined, and hell is as real as the nose on your face?” – What if God is purer than we thought, we’re worse than we imagined, and the hell of sin does not have the final victory after all? (After all, when God says in the Old Testament “My ways are higher than your ways, and my thoughts are not your thoughts”, He does so in rebuke against those denying the hope of salvation and preaching despair instead.)
“What if the “only way” means the only way?” – Christ is still the only way for any and all sinners to be saved, if Christian universalism is true.
“What if God is glorified in salvation and judgment?” – What if God’s glory in judgment is judgment (even in war) unto fair-togetherness?–as the scripture also teaches (including in RevJohn 19).
“What if the God of love and the Father of mercies is also a righteous Judge, a holy Sovereign, and a conquering King?” – What if the God of love and the Father of mercies does not stop being the God of love and the Father of mercies while being a righteous Judge, a holy Sovereign, and a conquering King, but is still also the God of love and the Father of mercies while judging righteously, and conquering in holiness, being sovereign in holiness? Does righteous judgment and holy reigning have nothing at all to do with love and mercy? Do we not pray in regard to ourselves that goodness and mercy shall continually hound us (pursuing to overthrow us, as in the Hebrew of that Psalm) all the days of our lives? Do we not praise God for the comfort of His rod of iron as well as of His staff?
Well, apparently most of us don’t!
But some of us do. 
Nothing speaks louder of Christ than walking in his footsteps. And, at the end of the day, what God really cares about is if we’ve loved, or believed in penal substitution. Ok, maybe not the latter. 
I’m so bad. 
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