1. They stated by decreasing inventory slots, they can generate more NPCs at any given time (as the fewer slots requires less memory per NPC). This is oberserved in how the civil war quests do tend to have a good bit of waves of enemies beyond what we saw with the battle of Bruma in Oblivion.
2. The enchanting skill would cause two rings to break the game even further. Duel effect would allow for some pretty broken overall effects to be applied to rings. +80% one handed damage +60 heavy armour total from my rings? Yes please.