I completely agree with you that we all cherish the victories we personally sacrifice for. That sacrifice helps us to savor our victories.
But, where I completely disagree with you is 'we can't appreciate God's grace without people suffering for eternity'. I'm going to leave a story based on popular Christian teachings below. If you were the "intruder" in the story, would you feel comfortable telling the "Dad" in the story that you couldn't truly appreciate God's grace without the "Dad's" eternal suffering? I know I sure couldn't. Let me know, though.
THE LOVE OF CHRIST:
One night a young girl is watching a movie with her kind and loving atheist dad at home. An intruder breaks in, brutally murders the girl's dad in front of her, and then rapes and brutally murders the little girl.
The intruder is never caught, but one day he finds Christ and makes him his Lord and Savior and turns his life around.
At the day of judgment, the little girl asks Christ why her kind and loving atheist dad is going to suffer in Hell for eternity and why the man who brutally raped her and killed her dad is going to Heaven.
Christ smiled at the little girl and said, "Because the man who raped and murdered you made me his Lord and worshipped me like I was God, and your kind and loving dad did not."
Does that sound like God to you? To me, that is as evil as it gets.
"Belief in a cruel god makes a cruel man." - Thomas Paine
All I can say is that I think that we don't have the full picture living here in our finite life on earth. We define good and bad from the perspective of what is good and bad from our point of view. Instead, what is truly good and bad is from God's point of view. Things are good because God says they are good and things are evil because God says they are evil despite of our personal definitions of the two. We look at death, rape and murder as the worst things that could possibly happen to someone when the reality is that according to the Bible the worst thing that could possibly happen to someone is to forfeit their soul by refusing God's sacrifice of Jesus Christ. We see things through our own eyes instead of through God's eyes. Even the story you shared was all about what happened "to" someone instead of focussing on the things of God. Was I rapped? Then thank God that is wasn't I that rapped. Was I murdered? Then thank God that it wasn't I that murdered. The sermons of Jesus were all about taking our focus off of what is done to us and putting our focus on what we do to and for others. Let God be the judge of others while we focus on ourselves. God even talks about slavery and lays out instructions on how to be a "good slave". Is he condoning slavery? No! He's saying, "lets stop focusing on how other people are acting and start working on you in the situation you find yourself in." I think that is the whole purpose of his parable of the workers in the field. I don't think his message is that we'll all get the same reward, I think instead his message is to stop looking over our shoulders at what others are doing and focus on ourselves. Of course, I'm just a human and could be wrong. Listen to what God says to you and decide for yourself. :) Here's the parable I referenced:
Matt 20:1-16
“For the kingdom of heaven is like a landowner who went out early in the morning to hire workers for his vineyard. 2 He agreed to pay them a denarius[a] for the day and sent them into his vineyard.
3 “About nine in the morning he went out and saw others standing in the marketplace doing nothing. 4 He told them, ‘You also go and work in my vineyard, and I will pay you whatever is right.’ 5 So they went.
“He went out again about noon and about three in the afternoon and did the same thing. 6 About five in the afternoon he went out and found still others standing around. He asked them, ‘Why have you been standing here all day long doing nothing?’
7 “‘Because no one has hired us,’ they answered.
“He said to them, ‘You also go and work in my vineyard.’
8 “When evening came, the owner of the vineyard said to his foreman, ‘Call the workers and pay them their wages, beginning with the last ones hired and going on to the first.’
9 “The workers who were hired about five in the afternoon came and each received a denarius. 10 So when those came who were hired first, they expected to receive more. But each one of them also received a denarius. 11 When they received it, they began to grumble against the landowner. 12 ‘These who were hired last worked only one hour,’ they said, ‘and you have made them equal to us who have borne the burden of the work and the heat of the day.’
13 “But he answered one of them, ‘I am not being unfair to you, friend. Didn’t you agree to work for a denarius? 14 Take your pay and go. I want to give the one who was hired last the same as I gave you. 15 Don’t I have the right to do what I want with my own money? Or are you envious because I am generous?’
16 “So the last will be first, and the first will be last.”