Very nice, except for one thing.
We've had at least one Pinkie episode already this season, but "A Friend In Deed" gives us some new things all the same. We get a little more info as to how other ungulates in Equestria function (the way a given universe works never fails to interest me), Pinkie Pie gets more character development, with some nods to the less cheerful aspects of her personality, and most important for me, every issue I have with her as a viewer is brought up and examined, and it's clearly shown that, in spite of her faults, at the end of the day she is
a very good friend to have.
The only problem I have is with the ending. For one, it seems like a cop-out, and an extremely obvious one in retrospect; Matilda is the first donkey ever seen on the show, and female, so it only stands to reason she'd be Cranky's love interest, and it feels like she was created for that sole purpose. If she had been introduced in an earlier episode, the whole thing might have worked, but here it just seems contrived. A much bigger complaint is how much more emotionally powerful and resonating the episode could have
been, if, say, the special friend had been Cranky's deceased wife. The concept of death does exist in Equestria, as shown in a blink-and-you'll-miss-it moment in the previous episode, and "A Friend In Deed" I think missed an opportunity to treat the matter in a more serious light. Cranky could have confided in Pinkie Pie, as she definitely has an understanding and sympathetic side, and we could have ended with, if not a full-blown grin from him, at least a small, warm smile at the comfort of having Pinkie always be around to brighten his day.
All that said, even if the ending didn't completely satisfy me, the episode as a whole did, and I think that's what counts.