"I applied my mind to study and to explore by wisdom all that is done under the heavens. What a heavy burden God has laid on mankind! " -Ecclesiastes 1:13Your beliefs don't stack up.
If I was an all powerful deity I would be able to avoid any such "tough love" situation without genocide.
So, in the face of the question of "why?" It seems that all answers are insufficient with you. Solomon, one of Israel's wealthiest kings, who reigned over a time of endless prosperity, experienced it all. The conclusion he came to is that life is meaningless.
The point is to enjoy it, you can choose to look at the world through a scope of criticism. You can choose to observe how bleak and futile life truly is, or you can choose to be grateful for the moments that you have and enjoy it.
"And said, Naked came I out of my mother's womb, and naked shall I return thither: the Lord gave, and the Lord hath taken away; blessed be the name of the Lord." - Job 1:21
Powerlessness does not come easy. It isn't fun to admit that really anything we have is a blessing and that it isn't by my merit that I have what I have. But only by the grace of God. But, if I start with that outlook, the world is a lot less bleak.