I was reading on Ryan Jordan's site a post about simplicity and at one point it questions the reader on how many items are in their pack: "What if you limited the number of items you carried in your pack to 50? 20? How about 10?"
I've been pursuing simplicity for the past year or so, but never added the number of items that I carry, so I added it up:
I normally carry 38 items.
4 main items (Quilt, Pad, Shelter, Pack)
3 Stuff Sacks
2 bottles (1 water, 1 fuel)
8 items of clothing (rain jkt, rain pants, down vest, spare shirt, 1 under wear, 1 socks, bug net, beanie)
4 piece cookset (pot, cone, stove, spoon)
8 health/hygene items (first aid kit, toothbrush, deoderant, toilet paper, hydropel, water tabs, soap, deet)
6 misc gear (bear bag cord, duct tape, fire sparker, lighter, knife, map)
3 electronic items (headlamp, camera, backup squeeze light)
Perhaps the sweet spot is around 30-50 items. It seems to me that getting the total too low might start to have a negative affect on trip quality/simplicity. For example, if I left behind my stuff sack that holds all my small items, I would have a harder time finding stuff. It wouldn't really be a simpler trip if I had to dump out my pack every time in needed to find something. Conversely, if you're carrying 80 items then you'd also have the similar problem of difficulty keeping track of all your stuff and again the pack might get dumped out to search for something.
I know compared to how I hiked a few years ago, I carry far less items and it's much easier to keep track of everything and setup/take down camp, which boosts efficiency....so I'm pretty happy at 38.