Petrus, I think if your going sailing for fun(which is all we do) take as much as you need to be comfortable, but as has been said judicious weight distribution is a good idea. I am a bit of weight nazi when it comes to travel of any sort but rather than not have something I need I look for the smallest lightest version of what will do the job. Lots of small things can be heavy. The thing that I have worked on in SPRITZIG II over the years was to take out anything we have not used in the last 12 months and try to keep everything in a place so it does not become clutter.
I've had 5 people on board at once but it was three in the cockpit and two teenagers on the foredeck ducking the jib which was not that often as we were on a long slow reach up the lake . You do notice the weight in light winds but who's is a hurry? My boat seemed to sail better when I ditched the monster truck battery I had in the rear lockers for a small motorbike sized one on the forward space when I switched to LED lights.
I remember I put a similar question years ago to my mate who does club race and so is in a hurry and he told me he was pacing another friend down the lake once in light airs, both in 27 ft keelers. He was solo but his mate had his wife on board. After 20 minutes of both holding the same exact speed he yelled at his opponent to send his wife forward. Slowly the weight shift made the other boat pull away. So obviously there's trim and speed gains to be had by even relatively minor amounts
If ever I'm in a hurry to get home, left the iron on or something, I'll send my wife up to the foredeck
Also this is interesting
http://www.ybw.com/forums/archive/index ... 32176.html
About half way down the page there is this statement, also food for thought.
"A heavier boat will have more immersed wetted surface area-so will be slower at low windspeeds- and will plough a bigger groove at higher speeds so loading up the rig and losing more energy just making waves. But the motion may be more comfortable so the crew happily press on in which case who gets there first, Jimi, the tortoise or the hare?"