Stephen Amell came out in the new costume and gave credit to costume designer Maya Mani adding that she:
Made every single suit on our show since the original Arrow costume. She nailed it.
Executive Producer Greg Berlanti said:
We’ve always said the progression for Oliver is very much from the Arrow to Green Arrow. This is first real stop in that direction.
Executive Producer Andrew Kreisberg added:
The show isn’t going to suddenly to become a comedy. When the season starts, he’s in much a better place. He’s happy. He’s in love. That feeling infuses all the characters. There’s a little bit more fun [and] more humor.
Oliver Queen isn’t the only one getting a new costume as it looks like John Diggle will finally have a suit of his own which the concept art for it has been posted online from various people that were in attendance at the panel, with many online believing that the look may be more in line with the look of Guardian from the comics.
There’s another big [DC character] coming. There’s a lot of characters coming up that people won’t really guess.
Also revealed was that two characters will be appearing in Season 4. Anarky, who is somewhat of an anti-villain, and Mister Terrific, who will be working with Felicity and will also happen to be the show’s first gay character. I’m not really familiar with either character but with the little that was talked about Anarky maybe perhaps he’ll be a one-off villain. As for the Green Arrow outfit I like and the Diggle concept art outfit looks just like a biker helmet to me but I’ll wait to see what David Ramsey looks like in the real thing.
Arrow Season 4 starts stateside in October.