I've grown to appreciate many types of girls over the years (even though I have favorites). Even at my heaviest weight though, I still would have been wearing the Peter Griffith "No Fat Chicks" t-shirt. I am ok with slightly heavier than normal, especially if it's just left over baby fat that will disappear over time.
One body type I love is that brief time when some girls start growing taller faster than their weight can keep up with them. They end up with long wiry arms and legs for a little while, although eventually their weight balances out again. I notice that this is a time when they get extremely shy about what their body looks like. I find myself wishing I could tell them how gorgeous it is to me. A few times I have encountered girls who were actually quite a bit taller than myself, and yet I knew they were around twelve or thirteen at most. Kind of thrilling for some reason, to be looking up at a LG. No further comment:) On the other hand, very short and petite also gets to me.
I guess overweight girls need the same feedback, especially when as you say, it is not eating habits or lifestyle, but just genetics.