What I Liked:
Brittana storylines
Tina standing up for herself + body swap ("Props")
TGP contenders' characters
Many of the songs
Samcedes storylines
Sugar and Rory first dating ("Heart")
Quinn and Joe storyline ("Dance With Somebody")
Every Burt scene
Coach Roz
Coach Beiste storyline
Brittany becoming class president (confirmed in "I Kissed A Girl")
New Directions winning all choir competitions ("Hold On to Sixteen", "On My Way", and "Nationals")
What I Disliked:
Finn proposing to Rachel ("Yes/No")
The domestic violence Cooter threw at Coach Beiste (or just Cooter overall)
Shane dominating over Sam for Mercedes
Quinn getting into the car crash ("On My Way")
Quinn's skank phase ("Purple Piano Project" to "I Am Unicorn")
Mercedes/Rachel storyline in "Asian F"
No one helping Brittany beforehand on her GPA/Brittany not discussing her problem with that earlier on ("Goodbye")
Chandler ("Dance With Somebody")
Anything with Sebastian
What I Would Change:
An episode for Blaine ("Big Brother") coming directly after Quinn's accident ("On My Way")
Eliminating "I Am Unicorn" and/or "The Spanish Teacher"
Change the whole plotline for "The First Time"
Getting Kurt into NYADA
Taking Chandler and Cooter out
Finn gets into Inside the Actor's Studio ("Goodbye")/not going to the army
Brittany successfully graduates with an accurate GPA
Tina gets more storylines (not just one episode)
More storylines for TGP contenders' characters
Santana doesn't hit Rory with dodgeballs ("Mash Off")/Sebastian doesn't slushie Blaine or Santana ("Michael")
More humor/comedy overall
I loved the development of all of the relationships. I love how much stronger they've gotten over this season. I also love all the finchel. If I could change one thing I would actually change two things I would have Kurt get into nyada and finchel would not have broken up.
I liked the conversation between kurt and rachel in purple piano project.
K: I am ending this pity party right now! Look at yourself, rachel. what do you see?
R: shattered dreams?
K: you're you, rachel. there is no one just like you.
R: well it's funny, because, apparently there is!
K: ok, so they are better than you. they have more talent. they have more experience. but you are feirce, rachel. your ambition does push ups while you sleep. nobody wants this more than you do. nobody. and you're not giving up on this, 'cause i'm not gonna let you
That conversation helped me in so many ways
I also thought the episode where the bully tries to kill himself was very well-done
Other than those, i didnt really like season 3. hopefully season 4 will be better
Liked: Music and new characters, plot after Quinn's goth moment, Sebastian
Disliked: Quinn accident, not enough Klaine (and their kisses!), where did Shelby go?!