Reshuffle control is the most universal one.
He're the thing that I wonder. Let's say that there was a kingdom card that was this. It costs very little - $0, perhaps, or $1. All it has is, +1 card, +1 action, and an on buy effect, which is when you buy it, you may gain up to 4 additional copies of it. Let's also say the kingdom pile is exceptionally large, 50 cards say. How often is it a good thing for your deck to pick these up with spare money, and how often is it a bad thing?
I suspect it's bad a lot more often than it's good - it clashes with terminal draw, with opponent's discard effects, all the other things we've noted in this thread and in the past. It's good sides - draw control, activation of things like Peddler, Conspirator, Throne Room, I think are more situational.