I do agree with you on quite a few points.
Although, really, saying 'mainstream' indie is a contradiction of the genre.
I guess you could say any band that doesn't have a label or a prominent style, could be called indie.
I know a few local artists that don't really fit into any genre, and indie is plainly the best way to describe them. That folkie-artsy-I-wanna-be-trendy sort of thing.
It's all rather fake. I haven't found anyone I feel is truely 'indie', as the genre describes. It's a bit of a joke.
I dunno.
I wouldn't call bands like Coldplay, and Snow Patrol, and such as indie, since they are very big word-wide known bands. Those sorts of bands need a new genre that doesn't contradict itself by definition!
I always saw indie as meaning unsigned artists or bands, who take on a slightly bohemian lifestyle, and try to write music that isn't just about sex, about life and relating emotions to objects. Aha. A local artist relates her last relationship to an old jar in her kitchen. I hate her music, so boring, so insincere.
Perhaps the hippies of today, except a bit less political and a bit less LSD?