>>34402124S4 is kind of limbo between pre- and post-Twilicorn. Golden Oaks Library still exists, and without the Map, most episodes still take place in Ponyville. Although there is also still plenty of new stuff (Comic world, Breezies, Daring Do). In a sense, it feels like a breath of fresh air (although that may be my bias, since I got on the ride in the pre-S4 hiatus. Twilight's princess status didn't really make sense, but at least they a) made it a theme of the season and b) tackled the issue later on, with her own castle and such. But even after that, they didn't make Twilight a true princess. She has no authority, no power of her own. She just has more unofficial authority and lives in a crystal tree now.
Both the opener and the finale could have used better writing. Twilight made strange decisions regarding her friends in the former, and the plot of the latter was rather contrived in general. Still, they weren't bad, I strongly prefer them to The Crystal Empire and the Crystalling. In fact, I'm still awed by the Twilight vs Tirek battle.
The Equestria Games arc was disappointing. Instead of focusing on the hype such a gigantic event, the episode was just about Spike making an embarrassment of himself, and not much in between. I think there was potential for this to be Best Night Ever 2.0. Rainbow Dash's Wonderbolts arc got considerable attention, and Testing, Testing 1, 2, 3 was good, but Rainbow Falls strongly tainted the luster of their name.
Best episodes: Pinkie Pride (10/10), Pinkie Apple Pie, For Whom The Sweetie Belle Toils, Leap of Faith.
Worst episodes: Simple Ways, Rainbow Falls, Somepony To Watch Over Me, Trade Ya, Equestria Games (which is a lot more than I tend to remember S4 for)