I am a die-hard pegasister. I have a ton of merch. I have dozens of ponies from almost every generation, and a couple of shirts. And funnily enough, I actually do perk up when I hear the word "rarity" or see Applejacks cereal! Haters used to upset me, but I've come to realize that every fandom has its share of haters and if you let other people dictate your likes and dislikes, you're gonna have a bad time. Haters gonna hate, so you gotta keep calm and get your pony on!
My favorite pony is Derpy/Ditzy Doo. I absolutely love the personality and life that the fandom (and, as of The Last Roundup, the show itself) has collectively crafted for her, such as her gentle and sweet personality, her love of muffins, her job as mailmare and even her daughter Dinky. I hope that one day Derpy will get her own episode. I also hope that more toys will be released of her. So far there have been two: a limited-edition Fashion Style Derpy that was sold at Comic Con last summer, and a Hot Topic exclusive all-vinyl toy. I missed the chance to get Fashion Style Derpy, but I ordered the Hot Topic toy and am awaiting her arrival in the mail. I hope that one day Funrise will release a plushie of Derpy. They have released plushies of several ponies (I own Twilight Sparkle) and I am very impressed with their show accuracy, size, texture and overall quality. If I had a Derpy plushie, I'd cuddle with her 24/7 and take her everywhere with me.
Sorry for rambling; I'm crazy for ponies (and especially Derpy!)