I sort of have to disagree with the main topic here, as well as the notion that they're using ''too many" Batman characters.
While it's true that a LOT of Batman characters are showing up in this series, most of them are established Green Arrow characters anyway. If anything, they're more DC characters than exclusive characters to Batman.
- Deathstroke is a legitimate villain of Green Arrow in the comics.
- Black Canary is Green Arrow's love interest in most interpretations.
- If I'm not mistaken, The Clock King was Green Arrow's villain before he was Batman's.
- Count Vertigo was a villain of Black Canary first, and then Green Arrow.
- Merlyn is Green Arrow's arch-nemesis and he gets the chance to shine beautifully in Arrow... and he's not a Batman character.
- We get Shado, Eddie Fyres, Roy Harper, and Speedy (if you want to count Speedy)... all original Green Arrow characters.
So I don't get the criticism here. If we're talking about Huntress and Deadshot, that's two characters out of dozens on this show. It is BY FAR more of a Green Arrow show than it is a Batman show.
If we're talking about Oliver Queen being "too much" like Batman in this series, he was CONCEIVED as sort of a "Batman-Lite" character anyway. It's part of his history.
I'd argue that this show is doing everything perfectly. They're nailing it. And if you look at lists of Green Arrow's enemies and supporting characters, the writers of the show really don't have much to work with. So I think they're hitting it out of the park.
When it comes to Batman, I'd say as long as this show doesn't use The Joker, Two-Face, Catwoman, The Riddler, and The Penguin, any character is up for grabs, in my opinion.