I would fully agree that in the next world for the saved, that there will be no possibility of another Fall and the only choices we will have will be good ones. Sin is intolerable in Heaven. Put it this way, is the freedom to sin actually a freedom that you would want to have?
I don't worry about my level of freedom in Heaven because, without sin, I see it as being better than now. Truth sets us truly free, and in Heaven that's all that's going to be around us. I have given thought to the question "will I still be me (without my sin)"? But I don't worry about it because the faithful man spends his whole life ridding himself of sin in the first place. Heaven is 100% God-given success in that. It's a can't lose. With no tears in Heaven, I figure no person has ever asked to leave. :)
One possible reason for God not to simply have created us into Heaven in the first place was to give us the experience of sin in the world, so that we could appreciate what we have in God and His love for us. Perhaps Adam and Eve didn't understand the situation they enjoyed because they had nothing to compare it to. But whatever the real reason is, I think God DID have a reason and I will look forward to learning it. :)
I thought the world to come will be the a new Earth and a new Jerusalem, not Heaven, except that this time it will be "just right." I believe the name is the Kingdom of Haven, not the Heaven itself.
This concept is a derivation of the Judaic messianic belief that the (physical) world will be transformed into the World to Come, where peace and happiness will reign forever. A new, and reformed world, where everyone loves God with all his heart and mind and soul and his neighbor as himself. We are actually capable of creating such a world if all of humanity truly loved God.
We have been given more than enough blessings and showered with all sorts of abilities and skills to make this world a true paradise on earth, where there will be no fear, no violence and eventually no death.
When we are given new bodies, we will not be floating around in the universe.