I may be biased, but I think Pai is one of the top. Her i12 and i10 throws guarantee her launches and explosive floors, along with most every one of her counters. Her ability to cover a lot of distance while juggling (_6P spam) also helps to make sure she always hits the blue.
That, and her juggles already involve floor damage, so getting a double 46H+K after a bounce into a 66P+K ender (which is really common and guaranteed after her throws/most counters) is a total of four additions of bonus floor damage. Plus, when you take into consideration that she has the highest damage juggle from the explosive fall (from what I've seen, at least), she easily gets damage on that stage.
Ayane and Hayate are also strong on this stage and deal big damage "easier" than who was mentioned here so far, Momiji is as well though. And no, Akira is the best character on Dangerzone as he has the easiest and most strategy to abuse for 100-200+ damage.
His 6T will guarantee him a ground bounce on blue tiles no matter what. Simply makes his tick throwing the strongest mind game and it is all he needs on this stage.