Ideally we'll get body types eventually which would likely alleviate the issue with Dragonborn being overly stocky. There's plenty of official dragonborn art that doesn't have them built like that second image so I am not too concerned about it.
My biggest issue with dragonborn design has always been the lack of tails. Reptilian humanoids just look... Off without them. The tail pulls the entire look together. Without them they look like humans wearing big lizard masks. Especially when wearing clothing or armor. The tail poking out from behind confirms in my mind that their body matches the head even if I can't see the body under the armor. It also creates a sense of balance as that long snout feels like it should throw the human body type off balance without some kind of counterweight to it.
All in all tailless dragonborn just feel unnatural and I don't like it.
Alas, that is the canon of Forgotten Realms. So until Wizards of the Coast add tailed dragonborn to the world we're pretty much out of luck.
