I'm really intending Seth to be more sly, less "honor bound" if that makes any sense. Kind of how like I intended William to be, but without as much guile.
Basically he's willing to exert his power and take less than noble means to deal with a situation, even if it makes his enemies and those around him hate him. So long as he comes out the victor and has thoroughly crushed whatever it was he was facing, he won't care.
Machiavellian basically. 
And then again, this was kind of a short fight, not a long one like the one between Alexandra and Adrian. If we hadn't been on a time limit things might have gone differently, but who knows. Guess we'll see if something else like this happens.