I pretty much pack the same stuff, no matter if its one or fifteen nights, even on day hikes I often carry the same pack, it keeps me pack fit (maybe!!!). On the odd occasion I only take a day sack, I feel naked. Below is a kit list from a recent 5 day walk up the WHW and a bimble on the Kintyre Way (Kintyre way by far the better walk)
I use Lighterpack.com to plan my loads, a really spot on site, unfortunately I can't figure out how to display the list on this blog, so I've resorted to good old fashioned screenshots, sorry.
Get rid of sleeping bag stuff sack, but it rains now and then in Scotland, and I'm a bit paranoid about getting it damp/wet. Something to ponder though.
Dump the pillow, No chance, i love it
Dump some stuff sacks, possibly.
Lighter bergan and sleeping bag, possible but i love them both and can't really justify/afford to change them for a gram or 500
Smaller power pack? Possibly but the EasyAcc keeps my phone going for a week easily.
Drill holes in my spoon, nah, yer ok.