This one might be a bit controversial as Chris Pine is technically already in the DC Universe thanks to Wonder Woman. But, if you consider that Jason Momoa is apparently being considered for other roles within this new universe beyond Aquaman, then why couldn’t we see Chris Pine as our new Alec Holland?
There are a lot of reasons why Chris Pine could be an amazing Swamp Thing. Not only does he bring that sense of maturity to a role, but he also brings fun as well. He can be both serious and comedic, which we love in a DC hero. And at the same time, we can absolutely see him as a scientist living in the swamp and ultimately losing his life while also allowing his consciousness to become the embodiment of the Swamp Thing.
We want the maturity of an older actor, while also having someone who can offer their voice to the role (because obviously once he becomes the Swamp Thing it is less about his presence physically). Considering Pine has already proven his heroic prowess in a number of roles, including a DC superhero movie or two, we know that he can easily be a DC Universe hero in his own right.
Perhaps the only issue here might be how much time he would need to devote to the character and any potential follow-up movies, especially since the Swamp Thing has partnered with other characters of the DC world before, including Justice League heroes.