I use a gamepad and use all 3 action bars fairly equally. I agree that it would be nice to have all 3 bars shown as it often takes me about 500ms longer to find the skill I want to use if I can't remember what action bar I had showing (e.g. When the action bar gets hidden when a mole goes underground and I need to find featherfoot quickly). The 500ms can be the difference between taking a lot of damage and taking no damage.

The bar hiding thing can get annoying too, although it is useful to be able to see when you're able to scroll through targets instead of scrolling through skills. Perhaps a nice solution to this would be to hide the action bar only while in passive mode. When in active mode have the action bar always showing, but have it greyed out when in targetting mode (ie. when the bar is hidden at the moment). Action bar would be reactivated upon selecting a target (or using a skill on the highlighted target for clickers). so, fairly similar to how it is now but with keeping the utility of the skill bar hiding.