well
Its a touchy subject matter, this. Everyone will give different advice, and none of that advice will be 100 percent reliable, because everyone gives advice based on their own identity and perspective. No matter how kind others words may be, they could still end up useless in solving your problem.
I suggest analyzing the concrete, the facts that you can count on to be true:
1. You are striving to make some kind of mark in a world of rabid mark-makers. No matter how great your art is, there are a billion other marks fighting it out every second of every day to get noticed and be admired. And this will never change.
2. "Success" has as many definitions as there are people. Some may consider rap to be EPIC FAIL and others will swear by it. Realize that no matter how much genius you put into your art, how it is recieved by another person is all about THEM, not you. They will look for something they can use emotionally in their own life, in your art. If it isnt there they will move on. Unless you are catering to them on purpose you will have a much much harder time appealing to mass people, which is waht many people consider "success" in the entertainment industry.
3. Realize that stigmas about certain kinds of entertainment being too "mainstream" are all perceptions created by the most mainstream tools ever created: the human mind and culture itself. Great art has been mainstream. Mainstream art has been garbage. Define what is great not by the method it has been spread (or not spread) by the money making end of the industry. Judge art by the level of artistry or lack of that goes into its creation. Judge by emotional content, not whether its on tv or not.
I am going to be honest with you, i feel that you are putting more emphasis on what people will percieve about your art based on its facetious elements, rather than the quality of the art itself you have created. But this is not an insult because its very common to feel this way. But that is good news, because that means you arent guilty of any of the artistic "crimes" you feel you will be judged by (being too mainstream/indie etc). You are basically fighting an invisible enemy that cant be beaten anyways.
I suggest that you realize that no amount of perfection in your approach to how to present you art to the public based on genre etc will have much effect on how it ends up being percieved. You are far more likely to find "success" and peace of mind working on being your own personal best at entertaining yourself. You, after all, are a human. You want a good song to hear. So learn how to truly entertain yourself, TRULY, and others will be entertained as well. But if you hate your songs cuase they are too mainstream or too indie or too whatever, then others will hate them for those same reasons because they, like you, are human.
If you spend your effort on trying to amaze yourself with your own art, you will be too busy to care what word defines your art, what genre it fits in, or what people think negatively about what you have created. But its easy to fall into those thought processes trying to help/hurt your art by "framing" it a certain way and defining it. I suggest listening to your favorite records and figuring out what it is you love about its contruction (chords, melodies, words) rahter than its style (album art, bands image, public opinion of it). Then apply it to your own art. Take what you can learn from what works, then fill in what doesnt with something else that does. Believe it or not, THIS is what makes a great artist from just a guy who wishes he was a great artist because he has alot of deep feelings about the world around him and wants to express them. If you seek to entertain yourself truly you will too busy to care what genre you are in, and you wont even care, because you will have realized how you progressed from one level of artistry to the next, and you will seek to progress even further now that you realized the method you ascended by. Ive found that most "stuck" musicians are stuck because they go about improving their art in inefficient ways, rather than that they have no talent or no passion or no ideas. Once you learn to learn, you will never forget. And thats when the real challenges of creating artwork begin.
So dont feel bad about defining yourself through a name somebody told you from tv, just creat something amazing and no one will care. In fact, theyll be even more amazed that it breaks genre barriers. Good luck. Hope some of this long advice helps you.