Okay now we're all over the place again.
I have tried to reassign the favorites key without success. There is something else inherent about the behavior of that command that interferes with key reassignment. Not that the function works reliably for me even when on default bindings, it does not, the assignments (some or all) disappear periodically, and I can't get dual-wield assignments to work *at all*, so I have to assign from the inventory. I will keep trying.
I have movement mapped to QWES, Favorites on A, Use/Activate on D, Shouts on V, FoV on F, Draw/Sheathe on R, Rest on T, Char Menu on Tab, toggle run on Caps Lock, Left hand on M1, Right hand on M2, Jump on Space, Sprint on Shift, Sneak on Ctrl, Run on Alt, Automove on C, Journal on J, Inventory on I, Magic on P, Skills on /... yeah, that's the important ones. The only issue I've hit with that setup is taking books lying in the open. I activate them, start reading, and can't actually take them with E or D. Have to rebind use to E temporarily. I have never been able to right and left click a weapon to dual wield it, but if I assign a number to a favorite I have two of and hit it twice I will dual wield.
Keyboard is vastly more efficient for almost all functions (which is why being able to have a ton of keybinds and mappings is so important in the first place).
Hell, this is the #1 reason to play games on PC. Graphics is a close second, but the utility of having several hundred keys and combinations (with Alt, Ctrl, Shift, etc.) is the definitive bonus of operating on a PC instead of a console.