This has nothing to do with generosity. If someone was to copy Rarity's dress designs and just used different colours, it would bother her too, wouldn't it? Like in this one episode where this pony used her special fabric for all her dresses without her permission. It did upset her, she wasn't okay with it at all. It's basically the same thing here. Artists invest years into improving their art, and yes, if you like someone's art you should consider paying them for it. Because it is THEIR art. They share it, but that doesn't give others the permission to just make bases of it, that's theft. Even if they credit the artist, if they don't want others to make a base out of it, that's their right. It's just frustrating if you invest hours in a piece of art, and someone else just traces it. That is unfair and rude. I'm sorry to hear you worked hard on your drawing, but that still doesn't make it right. And to be so rude to the artis, just because they don't want their art to be used without permission...Thought Fluttershy would've taught you something about kindness.
Yes, it's good that you deleted it, some people don't even do that. But just remember to stay respectful,okay?