I would argue none of the Mane 6 are entirely innocent either. All of them have had moments where they have lashed out at their friends for something that could either be petty or selfish, or an ideological disagreement.
Starlight has done some pretty terrible stuff. So much that despite her now being self aware that what she was doing was wrong and arguably for a dumb reason, and the fact that she is wholeheartedly trying to be a better pony after Twilight gives her a pardon for her crimes, she still can't totally handle the idea of being in charge of anything, and because of that often reverts to using her magic to accomplish her goals out of old habits. But the fact that she really does want to change even though it's been hard is what makes her a likeable character, much like how encountering situations that test the strength of their Elements of Harmony are what make the Mane 6 likeable.
A perfect unblemished character is a boring one.
If anyone claims to actually hate Starlight Glimmer for all the things that she did and the fact that she was forgiven for them, then the same logic can be applied for any of the other main characters. Sure, what the others have done in the past may seem minor compared to leading a cult or casting spells on friends, but the logic still applies.
Personally, she's not my favorite. But in my opinion, she is one of the most interesting characters introduced so far, and I really think that a majority of the people who hate on her are really nothing more than screaming autists who don't like change or the direction the show is going. If you have legitimate reasons for hating the character, then whatever, but that's no reason to be so autistic with your hatred.
Glimmerfags, you're alright in my book, and so is Starlight. Here's to more episodes with her in Season 7.Also, more green later tonight.