I have a few runner-up choices for best costume that I'mma post because... well, fuck it. I'mma post 'em, that's why. Consider these a "What look I'd go for if I were playing them in UOU" - or in the case of Batman, what look I'd go for if there were enough pictures of it.

[hider=Batman][img]https://vignette.wikia.nocookie.net/batman/images/3/35/Batman_Earth-2_New_52.jpg/revision/latest?cb=20120430185848[/img]

I used to hate this design and think it were something straight out of the 90's, but I quickly grew to love it. There's something militaristic about it without seeming too much of a departure, and it's one of the few Batsuits to pull off black-on-black in the comics well enough.
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[hider=Spider-Man][img]https://vignette.wikia.nocookie.net/marveldatabase/images/f/fa/Superior_Spider-Man_Version_1.jpg/revision/latest?cb=20130816002539[/img]

I appreciate any good costume that leans into a character's modis operandi (Batman Beyond, for example), and that's what the first suit that Otto Octavius used as Spidey does for me. It gives the classic look a legitimate run for it's money, making it look a little creepier, a little meaner, and overall more like how a guy with freaky Spider-powers should look. Basically, everything that would make The Bugle have a field day while also playing into Peter's love of sci-fi. Love it.
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[hider=Superman][img]https://vignette.wikia.nocookie.net/marvel_dc/images/3/3c/Superman_Rebirth_Vol_1_1_Textless_Variant.jpg/revision/latest?cb=20160604234626[/img]

Weird belt buckle that I'd photoshop out aside, there's something about this suit I absolutely love. It gives the blue in Clark's outfit a much needed starkness, given one of my pet peeves is a Superman whose blue looks positively flat, while also retaining the bright red elements and eliminating the trunks in a good way. I also didn't mind the boots, as I felt the red ones had been done to death. 
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[hider=Wonder Woman][img]https://i.pinimg.com/originals/0c/aa/e3/0caae3070af89f45c3beae0e191bdbc1.jpg[/img]

I know, I know. Blasphemy for including a design that isn't red and blue. But if Diana ever left the island of her own accord and didn't need to appear as a delegate to the US, this is how I imagine she'd look - fiercely armored and unabashedly Greek. The fact that this is Donna and not Diana aside, I love this.[/hider]

[hider=Iron Man][img]https://vignette.wikia.nocookie.net/marveldatabase/images/0/05/James_Rhodes_%28Earth-616%29_from_Invincible_Iron_Man_Vol_1_521_page_--.jpg/revision/latest?cb=20120622212345[/img]

As much as I can't get enough of the sleek red and gold designs to come out of the post-Extremis era, this little number that Rhodey wore during a brief stint as Iron Man really caught my eye. It looks like the greatest "in progress" suit that Tony never had, having all of the trappings of Iron Man while also seeming as though the inner layer is exposed, making it look more science fiction-y. It's like if Iron Man met TRON. 
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[hider=Batgirl][img]https://i.pinimg.com/originals/1e/60/02/1e60028c8ac60c8c2f44f14f9cca75ac.jpg[/img]

Likely to be my most controversial choice, but I stand by it. I've always been a fan of the classic black and yellow look for Babs, but this armored variation for The New 52 was one of the few positives of making her Batgirl again for me.
It looks functional and doesn't make Barbara look 14 no matter who draws her, which is why I'm one of the few to dislike the Burnside look entirely.[/hider]

[hider=Captain America][img]http://static1.squarespace.com/static/51b3dc8ee4b051b96ceb10de/51ce6099e4b0d911b4489b79/52faaaefe4b052e52da9c665/1392191292547/captain-america-the-winter-soldier-director-on-caps-costume-preview.jpg?format=1000w[/img]

Look, I love the stars-and-stripes. But if Cap existed in the real world and I got to pick his suit, this is friggin' perfect. It looks like a standard issue Special Ops uniform combined with a superhero suit, and gives Steve that militaristic edge that he'd need in a world long removed from World War II. This is basically the embodiment of the modern America in the way the original was the embodimemt of the 40's.
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[hider=The Flash][img]https://i.pinimg.com/originals/a3/a4/86/a3a4864b1ded4e9d6f93459dfa3282f1.jpg[/img]

While I've always liked the CW suit to a degree, it's always needed to look less like a motorcycle number and more like a suit that Barry puts on as one piece. The newest suit tried to do that and fell flat on it's face with a goofy looking mask, so this fan design scratches the itch I've had.
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[hider=Green Arrow][img]https://cdn3.whatculture.com/images/2017/07/a6266af6f93cb6b2-600x400.jpg[/img]

I didh't originally choose a favorite for Ollie, but far and away this is it. Part Longbow Hunters, part the classic look, this is why I'll never truly appreciate the look that Amell sports on television. This, for me, is Green Arrow: the former survivalist turned the Robin Hood of a town so bent that it needs a guy with boxing glove arrows to save it.
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