Good points. I instantly thought about people who were hiding Jews during Holocaust, or Galileo Galilei, who recanted his heliocentrism and lived, and Giordano Bruno, who didn't, and was burned at the stake for it. It's also worth noting that the midwives you mentioned refused to kill their neighbor and lied to save their lives, and Rahab made a similar contract ("Our lives for your lives!" -- Joshua 2:14) with their neighbors in vein of Exodus 21:23-25 (eye for an eye, etc.). And neighbors in Old Testament were only fellow Jews, their slaves, and all who submitted to them in fear of "their" God.

But I think that that Galileo vs Bruno analogy illustrates the problem with lies told to protect oneself, and their impact on a person, pretty well. I mean, denying truth must have left Galileo with a pretty sour aftertaste. Like publicly denying a relationship and then facing one's partner -- awkward to say the least. Moreover, even protecting one's life with lies because of acts of "illegal righteousness" puts one in a lot of stress, which is not exactly conductive to knowledge of God. In essence, it's pretty much the same situation as that of Jesus, who didn't deny anything and ended on a cross, and Peter who denied Jesus several times to save his skin for the time being, only to “went out and weep bitterly.”

All in all, I'd say that lies are always a slippery slope, because one may eventually start to believe them and then habitually lie to (not only) oneself, which is a surefire way to "perish." Well, where I’m from, we have a saying that he who lies is just a step away from being a thief and a murderer.