1-5 I'm pretty sure can be done via modding, I'm not the one who can tell you how easy/hard it would be.
6. I'm pretty sure companions don't have an inventory, they share yours, best bet is to increase inventory management skill.
7. one of the number keys changes your commands direction, I know 1 is everyone then 2-4 is infantry/archers/cavalry though not sure what order, maybe 5 is companions?
8. f1 is "hold this position" basically they all move to wherever you are when you issue it, won't be much help if everyone is already in melee range as they'll still fight and shoot at anyone withing range. It does help though if you want to charge ahead and take out whatever reinforcements haven't gotten to the battle yet.
Theres a post somewhere with a list of all the commands, hopefully someone with a better memory than me can link ya
Rey~