This was the ultimate Rocky story wasn't it?
It was inspiring with the training, it was inspiring with the fight, and it was about the characters and the characters are what makes a great story.
The down side was Creed, he was a little under-developed in this wasn't he? They make up for it in Rocky II, III, and IV, but in Rocky he felt like a faceless nemesis didn't he? He was Mohamed Ali without real depth in this and the story could have used to develop him a little more in the first one.
But... we got it in the sequels.
The biggest selling point was the love story... I know mushy, right? ... but they did a great job of making it awkward and at times intimidating as well as absolutely sweet and charming and it was completely realistic and believable.
You could sit down and watch it and understand how they fell for one another. You got a sense of who they were and that carried over into Rocky II... but kind of ended in III and we only caught a glimpse of it here and there until Balboa.
Still, it was the low budget movie that stole out hearts. And it was the inspiring story about the underdog, and Rocky movies are best when they inspire.