We have always felt safe in RP; however, cannot say the same thing about Phoenix!.
As stated, it is not truly "safe" anywhere is it? We have been traveling to RP for years, never as often as we would like. There have been so many changes over the years. We are not bar people anymore and typically bring most of our own food and cocktails, and just stay at our condo. Again, not because we are afraid but because we are on vacation and just want to chillax and enjoy where we are. Also, we have big doggie with us so that limits where we can go and what we can do. We usually stay on Mirimar because we enjoy the privacy and beauty, but we do drive into town and beyond, and have driven at night. I agree that because there are NO lights the roads are dark, and animals crossing can be dangerous. Also, as stated, we stay way Easter week/Spring break, just a bit too crowded for us. We also typically do not go in the hot, hot summer months for personal reasons.
This being said, we do not have children so I cannot speak on that. If you are hesitant, you should test the waters first and go as a couple. Talk to the people there and get their opinons. I believe if you are just aware and smart it is just as "safe" as anywhere else.