Don't think it's that overused, but things I dislike: 2 minute flashbacks, 5 minute OP/ED, 3 minute PV; most of the time making the actual episode last from 25 minutes to under 20.
Also, the most overused thing in anime: 25 minute airing.(give or take a few seconds)
And in most if not all battle-type animes: The character jumps from being shit to a overpowered mofo in 1/100 time anyone else took to get there. Prime examples are the holy trinity: Bleach/Naruto/OP. But I believe all are like this, except the ones that are already bad-asses from the beginning.
Abusive girls, abuse for comedy is overused, if they are going to have abusive girls, make a plot point out of it like Love Hina. People irl do not violently assault and kill the suppose pervert before they get raped.
(School setting)The protagonist (male) sitting near a window in the lower left side of the room. Actually I think Rei Ayanami filled that position in the Evangelion series if memory serves.
Animes that revolve around close to nothing that focus on moe girls. Yeah that's pretty overused lately. Rather see more cowboy bebop and samurai champloo over k-on and my little sister can't be this cute.
Vague power source- ever seen an anime where the main boss is so damn strong that not even a continental explosion can kill him, but then some retard uses some power that's fueled by "friendship", "love", "courage" and all that crap? This can really ruin a good anime and reduce it from royalty to garbage in a flash.
SOUL EATER FOR EXAMPLE
-no not the manga, the manga has stayed coherent at least and continues to astound. I can't say the same for the anime though. It had such a good thing going for it. It was action packed, it didn't lack drama and humour was always there. It was definitely one of my favourites until the time came when the most epic of the bosses got one hit killed by a fist wrapped with multiple layers of courage.
Lipstick- it might just be me but I find animes and mangas that place lipstick on the lips of their heroines as a big let down. I find the natural artwork better and those red jam on their lips just make them look slutty.
Cakes- unless it's a cooking genre anime this just takes me off the plot. You're advertised as a music based anime or at least to be in that genre so stop acting like a baking show... you know who you are!
Say what you will about things being overused, but that's basically what animanga is.
Think back to why you started enjoying in the first place. It's probably all those things that you're nitpicking about now, that made it enjoyable for you in the first place.