It's too early to say how all the characters compare to each other, and that Browny would be the only one deserving his own categories. I mentioned in the other thread I think 1. is the way to go eventually, maybe give runs more time in the oven though.
I understand having a variable for Character choice could maybe dilute the boards a bit, but the characters do each feel unique enough to me to where I think it'd be nice to have a board for each one. Not only a gun's main shot but also Overload varies quite a bit between each character, and mobility differs as well. The Hard Corps characters especially have a lot of mobility and a few unique mechanics.
My line of thinking is it's simply an extra thing the runner has to think about that's unnecessary, since you can mash through the results screen and splitting on a black screen is easier and requires less effort than keeping track of exactly when the boss's HP is at zero. I ran The Messenger and it ends on final boss hit but that game has an autosplitter which was really nice.
Edit: Though I guess if an autosplitter were made for this game it'd be set to split at boss HP 0 anyway. Ah well just a thought.
I think this is a much easier spot for runners to split and would lead to more consistent final splits. I know it likely won't be an issue as far as times are concerned but I think it would feel better.