Here is my two cents!
For Esther, I think she can definitely pull it off. She did great as supporting in Buang and Khun Chai Ronnapee (Where she can be really sweet). I do want to see how she'll do as a doormat.
For Sean, I don't know. I've only watched one of his lakorn (Leh Ratee) and I loved him in there. But he was such a happy, bubbly, and sweet guy in there.
For the 2008 version with Pong, I've watched this version first and I have to say that I love it. It wasn't too dramatic and not too much things to complicate the storyline.
Compare to the older version, I watched it after the 2008 version and I have to say that i didn't like it too much. The N'ek seems like she was H---Y when the P'ek harassed her. While in Pong's version, the N'ek seems like a shy and innocent and tries to get out of this grips. Another thing I dislike this version, was the N'rai's father turning into a rappist (which he didn't get to do the deed, so he isn't yet, but going to). Dislike how the N'rai's parents took the N'ek in and raise her to be a mistress for the N'rai's father's needs.
Now, for who I'd like to see act as Preeyacha is Mo. I see a lot of potential in her.
As for the P'ek, I don't know. Maybe First, since he's such a tall handsome guy. Pong was tall too, so maybe FIrst can pull it off too. (Don't know if he's contracted to a different company).
H---Y