How much the powder fills the case is not a good indicator of anything.
There is no special issue with compressing ball powders.
These two statements concern me, the second more than the first.
Case volume, & filling it consistently & accurately have been one of the standards of hand-loading for ever. Some manufacturers even list the % of load density as part of the load data.
As for compressing ball powder........ I still have both eyes, most of my face & all 12 fingers currently. I have no desire to change that situation.
Allan Quatermain: “Automatic rifles. Who in God's name has automatic rifles”?
Elderly Hunter: “That's dashed unsporting. Probably Belgium.”