Best costume change (that isn't reverting to an old one)

[Riv86672]

I'm sure I'm in the minority, but I liked Aquaman's blue costume.

^^^I liked it, too!
I think it was doomed in that it was too good for the era though. Not a lot of artists were going to do that design Justice.

[j9ac9k]

Nightwing comes to mind.
For sure he is not going back to disco neck or to pantless Robin.

John Stewart's modern costume with the black bodysuit and green pecs and shoulders is such a simple yet perfect look. Massive upgrade from his green-stripe-down-the-middle suit.

I agree with those 100%. I'll throw up Hal's update from Rebirth - getting rid of the swimsuit look by raising the green to waist-level.

Also, Green Arrow's Adams classic bronze age redesign with the van dyke

Captain Atom's redesign for the DC era - another "simple but awesome" design (with blue boots - for such a minimal design, changing them to red kills it for me):

[Dr. Poison]

This New 52 costume for Zatanna. Why DC got rid of it, I'll never understand:

[bat39]

Tim Drake's switch from his original red-and-green suit to the all-red suit during OYL. As a fan of the DCAU, I tend to associate Tim with the all-red suit and Dick with the red-and-green suit.

Not sure if it counts as a 'switch', but I definitely preferred Post-Crisis Superman's original all-blue Rebirth suit to the New 52 Superman's armor.

The now-iconic Mike Grell Green Arrow suit with the hood, which replaced the equally iconic Neal Adams Green Arrow suit with the hat.

Nightwing's iconic black suit with the blue emblem is definitely an improvement over the first two Nightwing suits IMO, and his definitive look for sure.

[K7P5V]

Hopefully this counts, but my choice would be Mary Marvel from The Power of SHAZAM! #28

[Alan2099]

Mr. Freeze.
First he had the yellow spandex suit.
Then he had that green jumpsuit with what looked like a welder's mask.
Then he finally got his DC Super Powers armor look.
And after that, the animated series outfit.

[Restingvoice]

Dick's costume have all been upgrades to me, not counting the one he goes back to

Robin
Pantsless Robin < Pantsed Robin with garish color < Modern pantsed Robin that's overly designed < Dan Mora's Pantsed Robin

Nightwing
Discowing with garish colors < Darker Discowing with mullet < Darker Discowing with mane < Darkest Nightwing with rat tail < Classic Nightwing but with bulky arm and legs for keeping tools < Red Nightwing with modern gauntlets to keep his tools < Red Nightwing with visible mesh on his armpits and joints to suggest easier movement < Rebirth slick costume < Infinite Frontier slick costume with tiny almost invisible backpack to attach his tools

This New 52 costume for Zatanna. Why DC got rid of it, I'll never understand:

Picture not showing
Is it the one with the cape? I like that one too

[Zero Hunter]

There have been a lot with the Legion but one of the best was Element Lad going from the Green/Dark Blue to the Magenta/Black costume. This is still the best look he has ever had.

[Digifiend]

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Yeah, please don't hotlink Wikia/Fandom, their images only show up if you have them cached from viewing them on their site.

[Kaijudo]

Nightshade's costume seems to change a lot from her original miniskirt look. The purple and black leotard job in Suicide Squad was a bit too generic for me, the pale skin and flowy half-dress in Shadowpact screamed emo/Goth a bit too much, the strapless bodysuit she had in the recent Deathstroke appearance feels too 90s Jim Balent-ish cheesecake for my liking, and the less said about the LAW look, the better.

But...her look by Ed Benes in the Superman/Batman book was a perfect modern update, in my opinion. Hearkens back to the original costume but sleeker and more practical, plus the purple-ish tint to the skin helps convey the shadowy nature of her powers better than pale skin does. Wish this one had stuck around longer.

nightshade.jpg

[Dr. Poison]

Dick's costume have all been upgrades to me, not counting the one he goes back to

Robin
Pantsless Robin < Pantsed Robin with garish color < Modern pantsed Robin that's overly designed < Dan Mora's Pantsed Robin

Nightwing
Discowing with garish colors < Darker Discowing with mullet < Darker Discowing with mane < Darkest Nightwing with rat tail < Classic Nightwing but with bulky arm and legs for keeping tools < Red Nightwing with modern gauntlets to keep his tools < Red Nightwing with visible mesh on his armpits and joints to suggest easier movement < Rebirth slick costume < Infinite Frontier slick costume with tiny almost invisible backpack to attach his tools



Picture not showing
Is it the one with the cape? I like that one too

Yes! Let's try this again. It's the one on the right:

[KC]

Neil Adams' Green Arrow costume over the Golden Age/Silver Age costume.

Hal Jordan's 2000s Green Lantern costume.

[Riv86672]

While I never had a problem w. Ray Palmer’s OG costume…


…I did like this Post Crisis redesign. The open cowl was a nice change, as was the fact that he could and would walk around at full size until it was actually time to shrink (I’ve never liked shrinking characters being in that state ALL THE DAMN TIME).


Edit:
Technically and by OP requirements I have to acknowledge that in between the OG and PC designs Ray did go Barbarian mode…:

[Mai Zen]

I guess it's arguably still count with OP requirements, I love Helena "Warrior Nun" Huntress outfit, or the similar one with the white cross

Yes! Let's try this again. It's the one on the right:

It's either Zatanna stage Magician or Superhero outfit for me, big no for ordinary street clothing like in the first half of JLD. I also like how she wearing the superheroic outfit as a symbol of her character development both in the 80s JLA and N52JLD

[Babylon23]

One of my favourites has to be Wally West's updated Flash costume after his first few years in Barry's outfit. Small nuanced changes that kept the essence of the original suit but enhanced it greatly.