Update:
You seem to be confusing omniscience with the inability to slaughter. God's only criterion was that some people choose to love him. God is not democratic. He did not require all of them to. In fact, some theologians suggest that only a third of all people will be saved.
The original:
Spoken by a Christian
The whole point of the problem of evil is this: God's goal with humans is to have us love Him of our own free will. He could, right now, command us to love Him. But that's not His goal - He already has all the love of that sort He wants, courtesy of every non-human object on earth.
Should have, hell! He knew about, indirectly caused, and was responsible for the whole Flood incident. No one ever said that the Christian God was a wishy-washy God. He's been pretty clear throughout that if you screw up, ever, once, you die, in a more than physical sense. After all, how can imperfection coexist with perfection?
He had Noah warn the poor bastards, but they wouldn't listen. God is pretty good about that, at least. He gives fair warning. See all the Prophets' books in the bible.
So, what was He supposed to do? Drop the matter? I don't think so. God doesn't go back on His word. So, He drowned 'em.
Being all-knowing doesn't imply being merciful. I fear God, and for good reason. He isn't to be trifled with. On the other hand, He's been kind enough to provide, to everyone who wants it, access to Heaven.
A God who is willing to let His only son die a horrible death to let people He finds repugnant into Paradise isn't a God who's gonna blink when He's taken up on His threats.
God may not have made us (well, most of us ;) brilliant, but He provides just about everyone with enough intelligence (and the clues) to make the right decision. (Personally, I think there are exceptions for those with major medical problems.)
Hmm... No one ever said that God was democratic. He's the ultimate ruling power, ever. Why would He let the majority make any decisions? He's aware of what each and every single person on the planet is doing and what they think about it. He lets each person make their own decisions. You don't enter Heaven by committee. You enter Heaven based solely on what you, and you alone, have done.