That thousand years is to allow the 'righteous' to 'grow; to perfection, in mind as well as body...
By the end of that time, the earth will have been brought back to paradise conditions and all people living will have ' "flesh fresher than in youth"...Job 33;25
This concept was even done in a "STAR TREK" episode, where the crew of the Enterprise came upon a people who were all young and unaffected by violence of any sort.
So the releasing of Satan...for a short time...is a final test for us...so it is NOT wise to thank that we already..."have iot made"...
It promotes humbleness, even when things are good.