I'm not sure if this is on the backlog; if not, I think it should be.
Many times during play, decisions are automatically made for the player. This occurs when there is only one choice for a decision (Lookout reveals three identical cards, I play Sacrifice with only Coppers in hand, etc.). As far as I know, there is no way to turn off this behavior.
This feature should be configurable. There are many reasons why someone would want to make each decision explicitly regardless of whether or not there's an actual decision to make. The most important one is that the interface would be more consistent -- for example, when I click on Salvager, the next card I click is always one that I want to trash, not one that I want to play, and I don't have to think about whether or not that decision is going to be made for me (are all of the cards in my hand the same?) before I even know what my next click does.
And of course if this is a configurable option, the default should be that no decisions are automatically made for the user.