As it is, we can only move objects up or down 1.00 from their default position.
It stands to reason why we can't move things DOWN below -1.00, but allowing us to move them UP more than 1.00 - perhaps a doubling of this to 2.00 - would still not allow any new abuse that isn't already possible given the height of most ceilings.
Some fixtures already have their base position very low to begin with, making it really hard to use them as intended (candles, houseplants, some paintings, etc.)
With the ease of use of the new NUI feature, it could make for a lot of interesting new layouts and setpieces.