Let's have a go at it and see! I have a feeling the "skill" and "aggression" thing they had going in the first one might have been overhauled, but nonetheless it's just easier to make vague comparisons to the PN1 cast.
I'll go first.
Brock: I'm thinking his cardinal weakness being that he's too honest and otherwise shows Tycho levels of early game aggression (read: little) and will generally go big only when he is absolutely certain he'll win. Might be surprisingly easy to intimidate, considering himself. He's the hardest to read from the get-go. I didn't watch all that much Venture Bros., cool as it was.
Claptrap: Strong Bad, full stop. Based on the trailer he seems to be more of his 'in-character' self from the games rather than the super primadonna of the behind the scenes stuff, even if the difference between the two isn't... great. So I imagine he won't be a very good player by any stretch but at least will play very fast and loose.
Ash: I'll admit I have never seen his movies, but if they're playing up the catchphrases and silliness and memes? I think he'll just play with the hand's flow more than anything, he'll try and check when people are playing conservative and if people are deciding to escalate, he probably wants to play big too so that his one-liners are loudest. If that makes sense, anyway - I don't think he'll instigate bluffs as much as Claptrap will but might see himself going out early as much as Claptrap might.
Sam: Something tells he he'll be of the 'try everything' variety as though he were treating this whole game as one extended sequence of a puzzle and is attempting to figure out the way through this particular segment of the imaginary episode in his head. So, probably a fair bit like Max in that he won't maintain the same particular strategy twice in a row (Max's aggression levels changed with every hand, which could make him do really silly things contrary to his actual hand strength). He may be sort of the straight man of his duo, but here I think he'll play just as unpredictably as he attempts to combine a 2 of hearts with a 7 of spades and hope for the best in advancing the story (spoilers: it won't, never play this hand).
What are your thoughts?