I am sure you have came to the right spot for your question. You should get a big variation of answer as this seem to be something that every back country camper I know is always changing and modifing what they bring.
for me and the people I have talked with their seems to be two main approaches that you can work with. The example I will give or at least me and my friends have fun with I will call:
1. The Boy Scott Approach - Be prepared for anything, and in my mind that ends up meaning bring everything you can imagine and stuff in your pack. This approach usually is better if you are just hiking into a back country camp and staying in one place the your entire trip. The more I bring the more I seem to like camping,
2. Second approach and the one that i did not start with but recently moved to is watch your weight on every item you bring. I like to call this approach "A country Boy can Survive". You will be suprised how much information is available on the internet and books about light weight back packing and to me has really been fun seeing how far you can take it. I less weight I cary the more I like hiking.
I started doing 6 day 5 night back country camping trips with everything needed for camping and fly fishing weighing in anywhere around 50 to 55 lbs.
Today I can do the same trip for 6 day and 5 night again with everything needed for camping and Fly fishing at 35 lbs. Now let me tell you 15 to 20 pounds might not sound like much but you will find that it is all the difference in the world.
One thing i found over the years as you dont need much planning when your pack weights in at 50 or 55 pounds but if you want it to come in at 35 you will end up creating a spreadsheet with every item and its weight. I would be glad to send you the spreadsheet I use if you are interested. Just email me at william.mclemore (at) ngc .com.
I am sure you will find others that have their own packing lists and you might find it interesting to compare different lists.
You would not image how much time and fun I have spent with this exact challenge of what to bring, how hard and far is the trip.