Well, it seems like a lot of those things will happen over the course of the series, Nos. It's only been one season and the creators already said the reason he hasn't been called Green Arrow yet is that he both hasn't reached that point and doesn't deserve to be called Green Arrow.
Also, since he's an established character and it wouldn't be his first appearance, I now wouldn't be against Amell in a Supermax movie, though I'm 95% sure that project's dead.
The main story is there just adapt it to fit the DCCU. Goyer's script was that good from what ive heard anyway.
There are a lot of reasons a film like Supermax would work.
It will be a relatively small budget action flick (50-60 million) that expands your very very small universe. It will not ruin anything, it will be in tone but you can't make it a drama or a character arc but you can make it an action film WITH great characters. Introduce Waller, great B villains, Task Force X and most importantly Green Arrow will become an Iron Man level icon . His *****ey personality, his politics and the fact that he fights for the little man make him instantly Superman's opposite, Batman's pal and a guy we can instantly connect with.
If I was given this story i would do it like this :
Ollie is the mayor of Starling City, him and his GA persona have cleared the city from mob bosses, illegal prostitution, drugs etc. Green Arrow is semi retired, he doesn't do any vigilantisms but he stays in shape just in case. BOOM, City Hall doors opens Detective Lance obviously frustrated, followed by Amanda Waller, followed by special soldiers and a few cops arrest him for vigilantism under the alias the Hood and Green Arrow. He is convicted and charged for life while Waller is pushing for a death sentance but Dinah's genius(lol) gets him life imprisonment in SuperMax.
While at Supermax he is being misstreated and questioned daily for his time on the island, him being arrow, his collegues and his involvment with project Justice League (here is your connection)(nothing else)
Months go by and suddenly Deathstroke from the inside stages a prison riot with B villains like Captain Boomerang, Captain Cold, Count Verigo, members of Checkmate, Onomatopoeia, Cupid and a few Batman villains attacking The Green Arrow. Prior to that Ollie using a few recourses he had left, contacts Felicity and contracts Deadshot into breaking him out of prison, possibly because he ows him one (we could assume, us who watch the show that he saved Deadshot from Diggle). So he gets to his arsenal, he becomes Green Arrow again and he has to go from point A (his cell) to point B (an office at the end of the prison where Deathstroke is)(boss battle) Traps have been set by the supervillains but also by Waller who watches the whole thing with cameras.
Anyway thats how it plays out in my mind. Like I said a pure action movie with great characters.
I know what the creators of the show have in mind but problem is the dccu cannot wait for much longer. something needs to happen.