I can definitely understand a lot of the complaints and I admit to mocking a lot of parts in my head as the movie plays, but overall I still find it fun and entertaining. My daughter loves it, dances to the music, and gets very excited watching it. She's 2 so the story and crappy Sunset Shimmer ending don't matter much to her. I actually enjoyed the humanized ponies. I thought it was fun seeing an alternate design for them and how they portrayed each of their personalities with their outfits.
The high school thing was kind of lame. Some things that bothered me with that:
1) In MLP:FIM the mane six seem to be the same age (or very close) as Cheerilee, yet in EQ they're teenaged students and she's an adult teacher.
2) The Cutie Mark Crusaders in high school makes no sense whatsoever (I know they were just thrown in there to say "hehe look! More characters you'll recognize!")
3) Principal Celestia was kind of a bitch.... Not the super kind, helpful Celestia we know.
4) No Discord.... but then again he'd need a really good reason to be there rather than just randomly thrown in the background just to say "hehe look! More chara---" oh, nevermind, they weren't too opposed to that method. So yeah, #4: No Discord randomly thrown in the background. As like a janitor or something.
Despite that.... I enjoyed it for what it was. My daughter enjoys it and we watch it often.
That frakking cafeteria song is stuck in my head, like, ALL the time.