TwiNet 
[@Background Pony \#24AB](/images/2714456#comment_9848929)
A Mary Sue (as based on the original Star Trek fanfiction that the term comes from) is best defined as a character who everyone likes unconditionally and always agrees with, with the possible exception of any villain characters who are vehemently opposed to them. Just from seasons one and two, I can probably find ninety examples of times Twilight and someone else disagreed, notably her friends, who you'd think would be the most likely to agree with her.
Besides this, she absolutely does face consequences for her actions, like in Winter Wrap Up when she's chastised for breaking tradition to try to fit in, or in Feeling Pinkie Keen where her own determination to break down reality into a cold hard science takes away from her enjoyment of it (represented by physical injuries). Most notably, in A Canterlot Wedding when, had Chrysalis not revealed herself, Twilight likely would have lost the support of her friends, family, and mentor all at once.
That all goes without mentioning that, on a more meta level, innumerable characters throughout the run of the generation have been forgiven for much more than is reasonable by our standards. Like how Sunset Shimmer by all accounts should have been arrested for destroying the entire entrance to Canterlot High, or how Starlight is forgiven when Twilight saw she was just misguided and needed rehabilitation. In any court they'd both be punished severely, but they were given the benefit of the doubt and given the chance to right their wrongs to prove they weren't being malicious, or in Sunset's case, that she didn't want to be malicious any more.
A Mary Sue (as based on the original Star Trek fanfiction that the term comes from) is best defined as a character who everyone likes unconditionally and always agrees with, with the possible exception of any villain characters who are vehemently opposed to them. Just from seasons one and two, I can probably find ninety examples of times Twilight and someone else disagreed, notably her friends, who you'd think would be the most likely to agree with her.
Besides this, she absolutely does face consequences for her actions, like in Winter Wrap Up when she's chastised for breaking tradition to try to fit in, or in Feeling Pinkie Keen where her own determination to break down reality into a cold hard science takes away from her enjoyment of it (represented by physical injuries). Most notably, in A Canterlot Wedding when, had Chrysalis not revealed herself, Twilight likely would have lost the support of her friends, family, and mentor all at once.
That all goes without mentioning that, on a more meta level, innumerable characters throughout the run of the generation have been forgiven for much more than is reasonable by our standards. Like how Sunset Shimmer by all accounts should have been arrested for destroying the entire entrance to Canterlot High, or how Starlight is forgiven when Twilight saw she was just misguided and needed rehabilitation. In any court they'd both be punished severely, but they were given the benefit of the doubt and given the chance to right their wrongs to prove they weren't being malicious, or in Sunset's case, that she didn't want to be malicious any more.