The biggest issue i have with a paradise on earth is twofold.
Firstly, is based off the infinite timeline = no matter how unlikely something will happen, it will happen, so everyone will sin, so no one will survive indefinelty. Unless of course, free will is removed.
Secondly, the limitations of the human brain, and the passage of time as we get older. I dont want a life 5 millenium down the line where everything is going through the motions, and it is literally impossible to make lasting relationships, and life becomes tedious. I believe that the knowledge of a finite end brings focus and structure to life, and makes it worth living; its adds some sense of urgency to everything.