gosh Faxman that is an interesting question yet a difficult one to answer without appearing to be rude or to offend you in anyway. I just didn't want to read this thread and not give my honest opinion. Firstly, I am by no means a perfect dieter or maintainer. I lose and gain weight and there has been a pattern to this and it is something I will always to to break the cycle of. So two reason for me to lose weight a) my terrbile relationship with food as I am an overeater and binge eater b) I am overweight for my height and frame c) I can feel the extra bits of fat d) as a result of all of this I feel bloated and unhealthy e) I have poor self esteem due to everything I listed previously.
In other words I don't need anyone to convince me I will feel better if I lose weight. Only I know that. So my answer to your question in your title " Convince me I will feel better for losing weight...." only you can answer. Do you really want to lose weight OR is it motivation you are seeking? Once you have answered that to yourself honestly then, you can find tonnes of motivation on here with all the diaries of those who are successful on the chosen plans or learn NOT how to do a plan when you look at my diary as I start ok then fail, and get into an awful cycle but I am trying to succeed this time. It's hard even with all the fantastic motivation on here so ultimately in my opinion we have to want to lose the weight before any of can stick to any diet plan or even make the right food choices so as not to gain any more weight.
I hope that helps?