Accept the Origin Story
As much as we'd like to just pretend that the first Green Lantern movie never happened, there's no use re-treading the same material so soon after it was first attempted. And even with the poor descriptions of the mysterious powers behind the green and yellow 'energies' of willpower and fear, the mythology behind the Green Lantern Corps was established in the first film, if not properly explained. So at this point, we have to disagree with those recommending a complete 'reboot' with a new Lantern (say, Kyle Rayner or John Stewart). Those characters have a role in the larger story to come, but there's no mistaking the fact that Silver Age Green Lantern (a time in which the cosmic plotlines were first established) Hal Jordan was the main man. Given that Geoff Johns' Green Lantern: Rebirth (2004) returned us to that point, it makes little sense to follow a completely new path on film. While Spider-Man might be able to endure the same origin story twice in the same decade, Green Lantern hasn't earned the same right. Our advice: now that the stage has been set for a film focused on story, not introduction, pulling a do-over isn't going to please a broader audience. Let's just move on.
Stick With Ryan ReynoldsThere were plenty of things done horribly wrong with Green Lantern, but casting Ryan Reynolds as Hal Jordan wasn't one of them. His leadingman status was never in doubt beforehand, but Reynolds' enthusiasm for the story and history of the character was clear from the get-go. Since the film's release, Reynolds has agreed with fan assessments that the movie didn't do justice to the comic, so blaming him for its problems seems like misguided anger. In all honesty, it's hard to think of a safer play for Warner Bros. and DC than sticking with Reynolds as their Jordan - he's the one they brought to the dance, he should be the one they leave with. His current fame as one of the sexiest men on the planet nearly guarantees that almost any movie would do better with him than without. The studio may decide to go with a different actor (and we've got some casting ideas if they do), but if star power can save Green Lantern, there are few bigger - or as interested - as Reynolds. There's no reason to think he'd ignore a strong script or director for the sequel - or an appearance in a Justice League movie, for that matter. That is, if he's not busy with Deadpool by then.
Bring Back Sinestro
Mark Strong's Sinestro hit almost every facet of the character perfectly. For the unfamiliar, his role in the first movie was as one of the Corps' greatest heroes, skeptical of humanity's potential but ultimately more willing to act than the relatively stoic, blue-skinned Guardians. In other words, the exact way we would have hoped. Audiences understanding Sinestro is necessary to make him a strong antagonist, since any good writer will tell you that complicated villains are the best, not 'evil' ones; a fact Strong clearly understood. As the closing moments of Green Lantern show Sinestro embracing the power of fear, and transforming under the yellow ring's influence, it was clear he was being teased as the next villain. We'd prefer a bit more explanation than 'the ring made him bad,' and as fans of the comics know, it's not hard to grow frustrated with those somber Guardians. You don't stall the story by making The Dark Knight (2008) without the Joker - and the same logic applies here. Of course, with the fight taking place so early in our hero's career, battling Sinestro seems like suicide; Hal's going to need some help...
Call in Reinforcements
We don't need to explain the potential for success that a spin-off Green Lantern: The Corps would have, since we know moviegoers love their team-ups. Strength in numbers is the reason for the Corps' existence, so it's about time Hal Jordan got some backup, and audiences got more characters to relate to. Starting with Guy Gardner: the man also chosen as Lantern of Space Sector 2814, with Hal Jordan's proximity to Abin Sur's ship the only deciding factor (a fact Gardner never let Jordan, or anyone, forget). Gardner's constant wise-cracking would also take the responsibility off of Reynolds, freeing him to focus on the wounded side of Hal Jordan's character. Add former marine and architect John Stewart - the Green Lantern of the Justice League animated series - and address younger viewers while including one of the all-too-few superheroes of color. If both were embraced by audiences, DC has even more options for the future. But what threat could demand the induction of two new human Lanterns? Perhaps the Guardians' mysterious actions coincide with the disappearance of Earth's most infamous villains? Humanity had better prepare itself...
Go To War
Any comic book fan knows of Geoff Johns and Dave Gibbons' "Sinestro Corps War" arc, not only for its impact in the series, but the DC Universe at large. With his Yellow Lantern Corps in tow, Sinestro plans to raze Coast City - Hal Jordan's hometown - as a galaxy-wide monument to the power of fear. A film based around Sinestro's army of psychopaths and murderers (awarded yellow rings for their ability to instill fear) would feature some incredible battles, but also allow Green Lantern 2 to act as glue between DC's movie franchises. Send the rings to recognizable villains from the existing DC movies, as the Earth's heroes are left wondering where their nemeses have escaped to. It would also give us a chance to see one of Sinestro's rings find Bruce Wayne, and the Lantern he might've made before rejecting the call. Obviously, the likes of Superman-Prime or the Anti-Monitor would be omitted from the pitched battle, raging on numerous fronts across the planet, all leading up to a one-on-one fight between Sinestro, Hal Jordan, and his closest friends. The citizens of the new 'Emerald City' refusing to abandon their hero is merely the cherry on top.