Posted this on another thread just earlier but applies here as well. We were talking about the use of shift/control/tab to give you 3 slot bars.
"meh. PC player who has been using controllers on nearly every game since my first Apple 2c. Controllers aren't what limits you to 8 slots. I played DAO with a rumblepad 2 and a creative xpadder profile. hint you can hit more than one trigger at a time to create even more profile modifiers. You can also use dpad macros to have as many modifier profiles as you can think of. So no consoles aren't the limiting factor. This was a design choice, whether by design or laziness."
Not to mention use of radial menus. With creative programming you can have every bit of control and pre slots that a KB/M can have.
In fact, I argue that controllers are better because they fit the human hand. Lets be clear we only have 10 fingers. On a KB you waste 3 of them just to move. Sure you have more buttons, but is it efficient? To me no. Therefore even though I'm a PC gamer I prefer gamepads. There is no reason why they couldn't have come up with a solution for say up to 16 to 20 quickslots on a gamepad. Totally doable and even if they didn't want to do that they could have used the radial menu to change quickslots during battle. Its not hard.
As far as the use of non quickslotted skills on companions. I wish I knew. I've seen both situations happen within my games, so I'm not sure which way is correct and which way is just bugs. Plenty of times my companions have done things not on the quickslot, but I'm not sure if its supposed to be that way.