I would seriously suggest cutting weight/getting in shape/ whatever to really bring out the best. I think visually there is also the proportion of stomach, ass, legs being smaller that, added w/ minimal fat pad, give the illusion of a bigger dick.
This helps a ton. I’ve been keeping in shape for 5 years now and before that I was a little bit chubby, and then when I slimmed down my unit looked bigger, even before I started to PE. Who knows, maybe when the next girl sees it, it will feel bigger because it looks bigger, and she will come back or more. The mind is a powerful thing!