I would a have a perfect world if nature is not harmed nor destroyed, all the people are at peace, no broken families, no discrimination, politics and religion as one, no natural calamities, everyone loves each other and no more hate and lies.
For me world peace would only make it a boring life, we need conflict, something to overcome to continue on as a species. We can't just sit around with peace with everybody "Living happy lives", we need enemies, we need corruption to overcome. Human nature provides this luckily, and we can continue with the very conflict that drives humanity forwards.
If the concept of deceit did not exist. You could trust everyone, even your enemies. We would not all get along, there would still be fights, and wars. Heart breaks would be very rare since people wouldn't be tricked into loving someone that didn't love them. Every one getting along would be very dull. No reason for innovation or creativity. Just take away deceit. I'd be happy.
The world will NEVER be perfect. The bible specifically states to "be not of the world" God made the world and had the Devil put sin in it. The world will always have sin, and since it always has sin it CANNOT be perfect.
The earth would be a perfect place when Jesus rules the King of Kings He. Is called .All people will bow and worship Him All people and animals will get along the lion will lay down with the lamb is an example no sickness there will be peace every thing we have we will keep wont ever be stolen or ruined or harmed perfect health no problems with any thing just bliss peace happiness comfort no darkness light no evil no pain no confusion and riches that would be the best life were God ruled the whole world and every one worshiped Him as it should be and will be