Please keep in mind, these are just my opinions. I don't give a shit if you agree or disagree. You have your opinions too.
1. Luna as a gamer. This one irritates me the most; I think it's because I just can't see it happening. It doesn't fit her personality at all.
2. Luna and Celestia fighting over cake. Why???
3. Molestia. It's just disgusting. Just don't.
4. Lyra being obsessed with humans. This one doesn't bother me too much, but it can get annoying.
5. The Maud Pie rock jokes. They're so cliche, that's all..Some of them are funny.
6. Ponies in socks. Yes, they do look adorable in socks. But I don't care anymore; I've seen it so many times, they stopped being so cute!
7. Views of pony plots. I understand people think it's hot, but it is SO overused. Go on Inkbunny and search for ponies; you'll see more interesting poses of sexy ponies there.
8. Making the rest of the mane 6 ponies alicorns. I wasn't even a huge fan of Twi getting to be an alicorn when it first happened... :/ I'm neutral about it now, but I'd like the rest of the characters to stay the way they are >.< Especially AJ and Pinkie, because they don't have a horn or wings, so if they suddenly became alicorns, well - you know how that would go with each of their personalities as they are. And can you imagine what Rainbow would do with her magic if she grew a horn? Yikes.
-- Overrated ships/Ships I hate --
1. Vinyl and Tavi. I'm sorry, but it is. They can be cute together, but sometimes I just wish I could see one of them paired with somepony else instead..because I never do (except for, very rarely, Vinyl paired with Neon, which I actually like the idea of).
2. Lyra and Bon Bon. Yes, they're cute together. But, again, I NEVER see them paired with anypony else.
3. Braeburn and Soarin. I always hated this ship... (But I like Braeburn and Strongheart)
4. Braeburn and Applejack, which, btw, is DISGUSTING. THEY ARE COUSINS. And for that matter, I HATE ALL INCEST SHIPS.
5. Gilda and Rainbow Dash... I actually just hate this ship too. :l Also, I really love Flutterdash, and Gilda was a fucking bitch to Fluttershy sooo..
6. Roseluck and Dr. Whooves. It's just cliche, since there's a Rose in Dr. Who. I also prefer Dr. and Derpy together.
7. Daring Do and Rainbow Dash. They'd probably never work. They're too similar, and I think they'd just drive themselves crazy trying to date each other. Plus, a writer and a Wonderbolt ??
8. Soarin and Spitfire. I don't necessarily hate this ship, but pairing two Wonderbolts is, again...very cliche.
There are probably more cliche ships/overrated ships I don't like, but I can't think of any more right now.. lol.. you get the idea, I think