the first over-nighter is the hardest. as in, just going. once you're on the road and moving, you will wonder why it was so hard to just go. kind of like biking to work - convincing yourself to 'just do it' is the hardest part.

the rules of three ~ as in, if I leave "this thing" at home so I don't have to carry it, am I likely to die?
apply the rules of three to decide:
I can live 3 minutes without air. Since I'm not SCUBA diving, I don't need the SCUBA gear.
I can live 3 days without water. Do I need to filter water? If not, don't bring all the filtering gear.
I can live 3 weeks without food. ..... ok, I'll take food on an over nighter. But I try to keep it light: ramen; bag of tuna; oat meal; instant coffee. Most of my bike touring will cross a coffee shop or restaurant.