I know what you mean but technically they never 'willingly' go to get punished. If anything its the audience who now have the influence on what they receive. They really don't want to do the tag game for example but if people want it they suffer for it.
Though Matsumoto understandably gets off the hook due to his past injuries, except last year with the tickle torture!
I felt we hardly got to see the involvement of the bet winners. Usually they showed up halfway through the whole thing whilst the staff handled everything. They would occasionally pop in to mess with the others, but that still kinda happens when the staff take out a couple of members and then have them re-enter with some advantage (e.g. costume gags etc.). It's just my preference of course, but I like seeing all of the Gaki cast throughout the special (for as long as they can manage it of course). The writer for the batsus is a long time friend of Matsumoto's so I'm sure Downtown still have an influence over the direction of the show.
For batsus based on 'losing', in a way the Kiki and Karuta Cards challenge episodes has aspects of that still (e.g. Matsumoto having to go on a date with Matsuko Deluxe). They even started introducing batsus for losing the Retro Gaming challenges (maybe just so they could flick Housei in the head though
). I wouldn't mind seeing more of that.