For starters, I think that the dark comedy needs to be maintained. This movie definitely should not take itself too seriously, however I also wouldn't want to see it turn into a campfest. I'd like it to be more like a Coen Brothers film than a Sam Raimi flick.

I think the most obvious edit would be with Kang-Woo. I probably wouldn't show that he wasn't abusing Tae-Ju; I'd have that be more of a shock. Also, I'd completely cut out all of the stuff of him reappearing in visions and all of the psychological stuff with him. I'd also probably lose the fact that Sang-hyeon was a priest. I don't think you can tread lightly with religion and leaving the priesthood in an American film.

The biggest issue in an American version, and an issue that I didn't really think of until typing this, is that they kind of need to explain why the doctors just let Sang-hyeon go. It seems really odd that they fed him vampire blood and then just let him off into the world. I kind of like the idea of switching it so that the main character did go to the clinic as a sort of suicide attempt but there needs to be some kind of reason why the doctors let him go. I'm sure the obvious American option would be for one of the other patients to also have vampire blood in him; he goes crazy and starts killing everyone, the main character saves the day but it is too late - everyone is dead. It would add an early action scene which producers would love. It would also cut down on the time of him realizing that he's a vampire, which isn't that bad. The focus could be more on how the main character, who couldn't find a way to fit in the real world, is now trying to find a way to survive as an unreal being. (Maybe it's here where he "finds" religion or, at least, tries to use it to help him find a place in this world.)

Another issue with the religion/hospital angle is that he would probably be a celebrity if he was the only person to survive a test like that. Once a few people learned of the healer, I'm sure the word would spread like wildfire. Granted, you could maybe go into reality TV as the new religion but that's the kind of approach that I think would take the film off in a completely unnecessary direction. It might be interesting for another film but not for a remake of "Thirst".

I also think the theme with the girlfriend could follow along the lines of "Revolutionary Road". She could be trapped in a marriage she never wanted and sees the vampire as freedom. Of course, once he frees her, he then starts trying to keep her from preying on humans. Like DiCaprio's character in Rev Road, the man who once symbolized freedom has become her latest captor. In terms of supernatural storylines, it's kind of a tried and true issue - the one person trying to fit in and another superperson trying to take advantage of their new found superiority but, off the top of my head, it's the best angle to be able to have the main character and love interest be adversaries yet still remain close. (For instance, I'd probably have him wander in to his apartment and find his friends sitting around for a poker game. It might be the girl's attempt to out the main guy as a vampire and force him to either kill or be exposed.)

In a smaller switch, I might have the Priest kill his mentor AFTER giving him the gift of sight.

I'm just spitballing ideas here but I'd be interested in hearing any other ideas or options for a remake (or just reactions to the ideas I threw out there).