Ok, so your first statement is actually your conclusion. As you are arguing in the negative (saying it's not true) it needs to be changed from a positive to a negative statement. The "individuals and groups . . ." part is redundant so I've taken the liberty of removing that. Your conclusion is:
Influencing the world toward perfection is not a worthwhile goal.
Only three premises are needed from your comments to support that conclusion. I've interpreted your comments, so although the words may not be exactly the same, hopefully the meaning is:
1) It is unlikely that all people can become enlightened/ peaceful.
2) Total world enlightenment/ peace is unlikely (from 1).
3) Influencing the world toward enlightenment/ peace is not a worthwhile goal (from 1 and 2).
But this is not yet valid, as the conclusion does not necessarily follow on from the premises. An additional premise is needed to bridge the gap between 2 and 3:
1) It is unlikely that all people can become enlightened/ peaceful.
2) Total world enlightenment/ peace is unlikely (from 1).
3) A goal that is unlikely to be achieved is not a worthwhile goal.
4) Influencing the world toward enlightenment/ peace is not a worthwhile goal (from 1 , 2 and 3).
In terms of soundness: it's reasonable to believe that 1 is true. Therefore 2 is true, because it follows on from 1.
In terms of premise 3, one definition of worthwhile is: "worth the time, money, or effort spent". Is it worth spending money, time etc on something that is unlikely to be achieved? Arguably it's not. On the other hand, although paying for a lottery ticket each week is statistically unlikely to result in you winning the jackpot. Could it be argued that a tiny chance of winning a life changing amount of money is better than zero chance, so the financial outlay is worthwhile? And what about someone who performs an act of heroism. Would we describe that act as not being worthwhile because it was unlikely to ever be successful?
Although the above argument is logically valid, the soundness of the argument (the truth of the third premise) is debatable. It's a matter of opinion as to whether a goal that is unlikely to be achieved is worthwhile. Therefore it's only a matter of opinion as to whether trying to achieve worldwide enlightenment/ peace is worthwhile. The only way to make the argument valid and sound is:
1) It is unlikely that all people can become enlightened/ peaceful.
2) Total world enlightenment/ peace is unlikely (from 1).
3) A goal that is unlikely to be achieved may not be a worthwhile goal.
4) Influencing the world toward enlightenment/ peace may not be a worthwhile goal (from 1 , 2 and 3).
But again, this reduces the argument to no more than a tautology. Effectively it says: world peace/ enlightenment is either a worthwhile goal, or it isn't. This is absolutely true, but is not very meaningful. However it is exactly what I would expect to see with any argument that has at least one premise that is subjective. Because the truth of such a premise cannot be reasonably determined, such an argument can only be logically sound if qualified with the word "might".