There's really no need to have a different gravity to get a lot of DMs.
If you want a lot of DMs, you could try using mods that has instagib parts like footmod.tbm
It's a little easier to get dm's on a higher gravity because you get more force from your hits. (especially when downward)
In a lower gravity, it's easier to move/jump around, but your hits have slightly less power.
Most replay makers that want their replays to be realistic have their gravity set at 0 0 -30. Personally, I also use this gravity because it's easier to move around.
[23:23:53] <AndChat|700625> Blue eyes ultimate dragon best card
[23:24:29] <AndChat|700625> You know the one with 3 heads
[23:24:39] <~Lightningkid> just like my dick
[11:35:40] <box> Hampa suck
[11:36:21] <hampa> not the first to tell me that today