I'm just going to put it out there. I dislike Ryan Reynolds as an actor. In every film I've seen him in, he's had a part in ruining it because of his performance (or lack thereof). His Green Lantern film was no exception. So now you're probably wondering "How does this lead to the opinion in the title?" (if you're not, please think it anyway for my sake). Well, despite the fact that Green Lantern was awful in every way, and Reynolds was awful in it, I believe that Ryan Reynolds should reprise his role as Hal Jordan for one simple reason: commitment.
If there's anything Warner Bros. has not done for their DC movies it's make a solid commitment to doing something. I think the right way to do this is the same way you get your friends to stop cracking jokes at your expense. Laugh it off. "Hahah. You guys are right, Green Lantern was pretty bad. We can do better than that". And then you make the commitment to do so. Bring your actor back, get a director that will kick his ass into playing the character right, and get people hooked into wanting to see him in a new and improved sequel.
What's good for the goose is not always good for the gander. We've seen 3 people play the Hulk to varied success over the past decade, and I remember not being the only doubter silenced by seeing Ruffalo's "Incredible" portrayal of The Hulk (see what I did there?) in The Avengers. But DC and WB, please remember, you're already rebooting Batman in Justice League. If you get a new actor for Hal Jordan, or replace Hal altogether with John Stewart or Kyle Rayner it's going to have a lot of setbacks.
Replacing Reynolds will only add to the weirdness. We're going to be put into a situation in which five to seven of the greatest superheroes of all time will need to work together. With the exception of Henry Cavill, we're going to need to get used to everyone in their roles. And If time is taken out of the film to explain who Green Lantern is it would be a damn shame. The same goes for replacing Hal Jordan. We would need to get into back story and all kinds of other things that would be completely unnecessary if they had just brought him back.
So yeah, you made a mistake. You dug yourself into a confusing hole by making an awful Green Lantern movie. But just don't dig another one. Going into the Justice League film with two established franchise actors will give it a much greater sense of familiarity, and a much greater sense of ballsiness. Hopefully you will stick to your guns, WB.
Thanks for reading.