Sadly, I thought this thread was going to be about the Jyoti Singh case. I think the publicity of that case made a lot of people fearful of Delhi buses in general. I feel terrible for her family.
To answer your question, I think if you travel in groups with someone who is familiar with the bus system, it might be easier to navigate. My opinion is that when traveling to any country, learning the transportation system is one of the very first things you should do in preparation. How do you expect to get around and stay safe if you don't know how to travel? It defeats the purpose of travel if you go unprepared in that way.
I am also interested in private transportation such as rentals, maybe taxis, and buses designated for tourism. If anyone has this information, feel free to share! Thanks.