Disenchanted is the one to start with, no doubt about it; then Fallen Lights. The other two aren't far enough along yet to really sink teeth into. Though The Unseelie starts promisingly. Which isn't to say, there's something wrong with Reaper's Bay, just that very little of it has unfolded.
Adulterous choices are clearly labeled with a flower, distinguishing them from romance options which are labeled with a heart, making it easy to avoid them. So thanks for that!