WLS is major surgery and carries a whole bunch of challenges and risks. But you already know that. You want to hear the positive side.
There really isn't much of a positive side, to be honest, except for getting rid of all the dangers that obesity carries. So if you want to see the positive side of WLS, the best thing (in my opinion) is to look at the negatives of staying heavy, of which there are many. Your doctors can probably tell you more about them than I can -- and I'm betting they already have.
Good luck!