In all honesty, I think this whole season in general just hasn't been very good so far. Don't get me wrong, the episodes aren't terrible or anything, they're just nothing very noteworthy either. I'm not sure if I'm just becoming jaded with MLP or what but I haven't enjoyed these episodes as much as I've enjoyed past ones.
One problem I had was actually with one of the earlier episodes of this season. The one with Maud Pie. I don't dislike Maud but I do think she's a pretty one dimensional character. So much so that it almost feels intentional. Her obsession with rocks was cute and even kind of funny at first but now it's just tiring because that's really all there is to her. Rocks. Every sentence that comes out of her mouth has something to do with rocks and it's just really not that funny anymore. I've noticed the same thing with Twilight being so obsessive compulsive about making sure everything is just so. It used to be a cute quirk of hers that gave her more character but now it's starting to feel like that is her character. We see this in the season six opener and we even saw a little of it in the latest episode.
Characters like Pinkie and Spike also fell into this trap albeit a bit sooner than a character like Twilight did. Pinkie used to be the lighthearted jokester who wanted to make others laugh and be as great a friend as she could be. In the first season, we see that even though Pinkie loves pranks, she still knows when a prank goes too far such as when she decides not to prank Fluttershy because she thought it might hurt her. That really showed depth on Pinkie's part and made her that much more likable.
Then three seasons later, we have Pinkie just completely unaware of Fluttershy's feelings in Fili Vanilli. She scares Fluttershy so much with her insane what if scenarios that she, on numerous occasions, drives the poor pony to tears. And THIS is the same pony who didn't want to pull a prank on her friend because she was afraid it would hurt her feelings?
Spike, while I don't think he's necessarily been flanderized, I still think he's been getting worse treatment over the course of the show. In the beginning he was pretty much the little brother of the Mane Six. He could be a brat, laughing at their misfortunes (i.e after the poison joke messes with them) but he still clearly cared about them and they still clearly cared about him. By season four, it seemed like he had become the punching bag of the series. Most of the jokes that involved Spike were usually done at his expense.
But my biggest issue with MLP right now is that when it comes down to it, MLP just doesn't take any risks. I'm not saying it should be like Animaniacs and include more subtle adult humor or be like say, Batman the Animated Series and have dark, depressing storylines but just something a bit different. Lauren Faust once said that she originally wanted the characters to have more adventures so why not do something like that? Have them go on adventures, have them fight villains more often than just at the beginning and/or end of the season, have them go to other parts of Equestria(they've started doing this a little more which I think is pretty cool). I don't think slice-of-life stuff is bad, per se but I liken it to cake. It can be good and anyone can enjoy it but it's not something you should always have. It's good as a once in a while thing.
And maybe have an episode where not everything is wrapped up neatly with a pretty little bow on top. One thing I loved about the Reflections Arc in the comics was that not everything worked out perfectly in the end. A sacrifice had to made and there was no deus-ex-machina to reverse it. The arc had plenty of plot holes (one of which relates to the previously mentioned sacrifice) but I still enjoyed it. I won't spoil anymore but I thought it was a good read. Not outstanding, but good.
Anyway, point being, the series did use to do this with the ponies entering a competition and not always winning in the end (although that's changed too) but why not do that with more scenarios? Maybe have a friendship problem that starts to be resolved but isn't fully resolved at the end of the episode? That would be a great lesson for kids too that sometimes problems aren't solved right away and it can be a gradual process.
Even with all that said though, I do still enjoy this show and I do still love these characters. I just want to see more done with MLP. The series still has so much potential left in it and I just want to see that potential utilized.