I wouldn't be embarrassed one bit. I would be proud to own an interesting piece of American firearms history and the patina on your gun just show that it lead a working guns life. No signs of real abuse, rust pits or ding marks, but obviously has some mileage.
Looks great for being around 100 years old and a working gun. Plus you got it at a decent price. You couldn't buy a modern equivalent model 15 for the same price unless it was missing just as much blue and it wouldn't be anywhere near as interesting or shoot any better.