1. Extended Cross Hotbar.
2. I'm not sure if you are on playstation or PC using a game pad. There is a function called "Assist" that switches your target to your current target's target. On Playstation, you can do it through the system preferences.
3. Target filters for scrolling with left and right on the d-pad. I forget what they are called, but they are changed by holding L1 and pressing one of the shape buttons. You can customize them in preferences (might also have to do something to enable them). Basically, you can have left and right cycle enemies, then up/down can still do party members.