Adjusting the jump is going to be a massive pain mainly due to Lala needing to be able to jump as high as other races without looking strange.
Also the other races have to have a respectable jump as well, making it even harder to balance the hight of the jump. Chances are regardless of how much balancing they do Lalafells will look like circus midgets when they jump or taller races will look like they are just "High stepping" over fences.