I think it stands as no secret that the world could be a much better place. Humans could be more empathetic to both the people they meet and the ground they walk upon. We could look to the future by seeing the past instead of "guessing" and repeating it. All things considered there is a lot of negativity in this world of ours, and most of it is our doing.
In the past, I've regretted doing a lot of things. I mean, obviously. We all have. But when I look back I wonder if the mistakes I've made haven't lead me down some better path. Maybe the world isn't as great as it could be, but I honestly believe that the world is as it needs to be. If horrible things hadn't happened, people wouldn't take action to prevent its repetition in the future.
I know that sounds stupid, but let me put it this way:
Lets say, long ago, a cobbler's town was pillaged by a group of thugs. Lets say his family died in the attack. So, he goes over to the neighboring village and meets another guy, say a farmer. Having nowhere else to go, they become friends and start discussing why people are so awful as to pillage a town and kill innocent people like that. So they go to college and learn philosophy, where they then write a novel that becomes a classic that influences the hearts and minds for hundreds and hundreds of years on. Maybe the minds that book touches would have grown up to hate without that book. So maybe, in a way, that original atrocity saved countless lives of people that hadn't been born yet.
That's how I see the world. Sure, people suck, but they could be worse. Maybe this job that I have that I hate will give me the opportunity to get an awesome job later. Like, if I got a job I was somewhat content with, I wouldn't be prompted to leave and look for what else I could do. (That example isn't as strong, but since its a real world application of my theology, its more relatable.)
I can think of examples like this all day, but this line of thinking is what I have faith in. The world isn't perfect because perfection is a myth. I believe that if life was easy for all of us, we wouldn't grow as a species as quickly as we have. Like if we didn't have arms races with other nations and accidentally develop cool every day technology, we would invent and progress more slowly, and I believe that as the human species advances the average quality of life increases. So the faster we advance, the higher that average gets. So if we were all nice to each other from the beginning, maybe we would still be back in the dark ages. And as cool as that sounds, I like my daily hot shower and warm bed, thank you very much.