Applied Energistics Priorities Question

I know it can be done...But this is what i would like to do. I have looked around and i see stuff about priorities and storage busses and whatnot. but i cant put it all together in my desired layout.

I would like to keep a Larger Barrel full of cobble, that can be access by the system. and have the excess be send to packagers for compression.

the similar thing i want to do is to have a few barrels full of mob drops from my cursed earth farm but have the excess be sent to the Condenser for...

Applied Energistics Priorities Question