You guys are dreaming.
DC was bigger than Marvel in the beginning. Not only that, DC would sue any comic company that copied their superheroes ....shutting down many comic companies as a result.
Because of that Marvel had to get creative. They decided on creating characters that were more relatable ...more "human and flawed" compared to DC's characters that were more like gods than human. That's why they created the Fantastic Four, Spider-Man, X-Men, etc. None of those were copies of DC characters.
In fact, creating more "human and flawed" superheroes made Marvel a success. It made their superheroes more relatable. And it help Marvel grow to be a direct rival to DC. When DC realized they were losing readers because of that, they followed suit and tried to make their superheroes more relatable too. They copied Marvel ...and if DC didn't do that, they would've lost the fight.
Now ...did Marvel copy DC in some ways? Yes.
But you better believe DC copied Marvel in some ways, too.
You do realize you can't keep the characters the same from when they where created because over 80 years time change and you need to adjust to suit the current times hence new 52 and rebirth (major overhauls). Maybe Marvel did that first i am not sure. Marvel have had firsts in the comic world not just DC.
Anyhow what doesn't change is Thanos is a copy of Darkseid, Deadpool is a copy of Deathstroke etc. Now i don't mind the comics doing that because i enjoy the stories of DC and Marvel but what i do mind is people telling me they didn't copy and bring out all the excuses to make their claim valid which it is not.