You know, I sympathize with the desire for keeping people honest and well-meaning. I truly do.
Yet at the same time, I don't think simply being careful to follow certain rules is very useful.
Rules are no substitute to inspiration, nor to moral virtues proper. At best they work as deterrents to avoid harm when people aren't capable of knowing better by other means.
If I can give myself as an example, I can easily feel attracted by women who cover most of their faces but their eyes; eyes are often very exciting indeed, and most men can tell you how difficult it can be to avoid imagining the charms of a hidden body. Yet I have also on occasion had the opportunity to peek at the bodies of women that I know for a fact to be very attractive, yet chosen to avoid doing so out of respect.
Granted, I don't personaly believe that it is necessarily disrespectful to appreciate the beauty of a woman who is not my wife or close family. But neither am I unaware of the dangers of going by my instincts alone. Respect is not at all the same thing as obeying rules.
What I mean is that I don't expect people to rely on rules for me to behave, nor do I think any rules would necessarily make a better person out of me. Rules are often, if not usually, prone to misuse and abuse.
When you believe your values stem from a divine revelation, that makes them immune from being changed
It is my understanding that this statement of yours is a fair description of the Muslim stance on that matter, but isn't it a bit more specific than just being originated by divine revelation?
It could conceivably happen of moral values learned due to a divine revelation being valid yet also suitable to some degree of revision or perhaps even becoming obsolete due to cultural change.
For what it is worth, it happens often enough with human laws.