Can't help but still find Bronies creepy to be honest, it's not that it's males liking something aimed at a female audience, it's not that it's adults liking a cartoon for kids, it's both of those things together combined with the blatant sexualization of it all, which is creepy because we're not talking the usual furry anthropomorphic thing, the ponies are not anthropomorphic at all, how can someone honestly say they're turned on by that?
So to reiterate, it's adult males sexually attracted to cartoon characters meant for little girls, like 10 and under girls, creepy, creepy, creepy.
It's a bit worse than that.
Full disclosure is I used to be into the MLP thing (though even at my worst I never got into the sexualizing/fetishizing as beastiality makes me throw up, literally--and I'm using the dictionary definition of "literally" there). I just thought it was adorable, plus I had a young niece who visited often and it was a fun way to spend time together.
Which of course meant I sometimes talked to bronies online, and it's not just the sexualization that sucks.... Bronies are basically unable to handle any kind of differences of opinion or have any sort of adult debate skills, and are notorious for harassing people over very minor differences of opinion. One case you can look up is the Fimfiction user Chatoyance, who was one of the few who didn't like how the show's canon was so contradictory (other bronies usually treat the writers almost literally like gods or at least high priests and thus anything that's put on screen is right even if it makes no sense... and even when those same bronies say they don't even care about the show, just the community). This minor thing so irritated people that they made entire sub-groups dedicated to attacking her, which she informed the higher-ups about, but said higher-ups let said groups off on technicalities.
There was actually even a group on that same board for people like her who were dissatisfied with the show's direction (itself an argument not worth going into because it amounts to overanalyzing a cartoon clearly nobody on the producing team cared one whit about) and the behavior of the fandom. This place got raided on a regular basis.
And speaking personally, I've had Bronies follow me across the web even to places like my youtube channel (which has absolutely no MLP content and is under a different name than what I used for my brony interactions--even when I was a fan I was smart enough to realize I might want to break association someday--so I'm not sure how they found it). For awhile I had to lock comments.
Bronies, I found, have a couple of irritating patterns:
1. They will always, always try to claim they're more "mature" than you, for any reason... even for things they themselves are doing.
2. They have a bad habit of making assumptions, such as "you're just mad it violated your headcanon" (this usually in response to pointing out the show's continuity flubs, of which there are many) or accusing people of hinging on "the holy word of Lauren Faust." My friend Geo--who never was a hardcore fan and was never in the community at all--got this one on a non-brony forum, and his immediate question was: "Lauren Who?" He didn't even know who that person was. It didn't stop the bronies.
3. The thing which at first made them infamous was Bronies have a habit of inserting themselves and their show into literally any topic, for any reason. Just for example, on Digitpress I once mentioned some import games I saw at a store, and accidentally wrote Derby Stallion as
Derpy Stallion. Suddenly the thread became brony memes... on a video game forum, in a topic that had nothing to do with MLP except for a typo. People tried to explain to them why this was annoying, but they either didn't get it or were willingly obtuse.
4. This often comes up in relation to the previous, but they love to pretend they're being singled out, or otherwise use the "other fandoms do this too!" argument as if that makes anything okay. Several places noticed a hypocrisy about this, as bronies also like to claim they're unique and cite all sorts of positive values that don't really apply to them, but that they want people to think do.
5. They love to restrict speech, and the more lies their reasoning is based on, the better. Someone had a video on youtube (I think it was called "The truth about the brony fandom") where they--a brony themselves--identified harassment and bias from the higher ups at a con, and there was another guy who, after a very minor quibble (which actually ended amicably) bronies wound up trying to take his channel down. Because he said something they didn't like. It was something minor, like accidentally using a word he didn't realize was a slur or something and apologizing when the error was pointed out.
I could go on, but this stuff is well-documented across the web.
The cartoon itself is just an average modern cartoon, honestly its little different from Teen Titans Go (which ironically many bronies hate), except that it has pretentions of worldbuilding and continuity and moral themes, but when you look at the substance, it's clear that Equestria is every bit as dark and mean-spirited as Jump City, no matter how many times they use the word "friendship." Just look at the episode where they're tasked with trying to befriend that chaos serpent--their first thought is to simply brainwash him. Because that's what heroes do.
Teen Titans Go, at least, has no pretentions--it openly admits that it doesn't care and that it's heroes are jerks and just rolls with it.
As for this Unikitty thing, the first thing I thought when I saw a preview was "oh my god, Brony bating" and instantly decided I didn't want to watch it or have anything to do with it. I hope it crashes and burns.
EDIT: My apologies if I'm making my hostility far too obvious, but after my experiences, I can't find it in me to tone it down, any more than you could find it in you to not be hostile towards high school bullies or child killers. For what it's worth though, I draw a distinction between "Brony" and "Someone who just happens to watch MLP," and I don't mind the latter.