I think this is a very enjoyable action flick and I have no problem with Seagal being killed early on; that was the point! It was the equivalent of Janet Leigh being killed at the opening of PSYCHO, it is designed to surprise and shock you. Just as you think Seagal is going to save the day, he and his team are wiped out and it's left to Kurt Russell to save the day.
The mistake in the casting is not Seagal, but Russell. We've seen Kurt Russell handle himself in action flicks in the past, so he's not entirely convincing as a wimp turned hero. They'd have been better off casting a star not noted for having made an action flick in the past and it would have freshened things up and made it more interesting.