1. This is Early Access, and the party is limited by that, for now. We have no idea how many other companions are coming in the later acts, if any at all.
2. This already exists, in the Options Menu, and I think it's UI. There are some checkboxes you can hit that turn off automatically adding things to the hotbars.
3. Sure, why not. One can also just choose to take long rests as they feel are appropriate. The irony of all the things people want to add as an "option that can be ignored if one doesn't want to use it", such as Fade to Black sex scenes, or party size being acceptable, but "if LR abuse is troublesome for you don't abuse it" is somehow unacceptable isn't lost on me.
