This is actually something I've thought about for ages.
I do like just the background going black, but what I don't like is how it chops the floor up. It gets cut at sharp angles across the board, but one instance that sticks out in my mind is Scorpion's 2nd fatality in Jade's Desert. The background goes black and you can see all those nice wind effects, but then during the fatality the floor actually separates from itself, which looks very ugly. I can understand why it happens, but I'd still like them to fix it. I hope it doesn't show up in the final product, but it's possible they could just leave it due to most people being too busy watching the fatality to pick it up. Even though I can't see how anyone could miss it...
Bottom line, if they can resolve the edge problem, then I'd like them to keep this style. If not, make it old school 50% dim if possible.