Best money I ever spent on my LWHC was to replace the seat with a Hunt Comfort pad.
I still can't believe I spent that much on a seat pad, but man oh man is it worth every penny. I got the one that's 3" thick with the areo gel.
No problems at all sitting for the long haul with it, I recommend it to anyone who's rear goes to sleep after an hour...
Curt's trick with the bungee cord works great too - I had to switch to a bigger bungee cord as we've got some big trees out there. I also don't bother collapsing the stands anymore, I just leave the base locked open, and hang the seat over the arms with the pad facing into the stand base. Then use the bungee to hold the seat tight to the base - makes a little pocket that can hold a bag as the seat becomes a shelf.
A lot less tinkering when you get to your tree too! Unhook the bungee, open the latches and get the stand on the tree!