I also think the hut is a good idea but i'd like to make a few points.
The person who's name on the rental has full responsibility for cleaning damage etc.

There should be a kitty paid in beforehand as drinks etc will need to be purchased and cooled before party.

The more the merrier on the hosting commitee otherwise someone is going to need a whole weekend organising cleaning etc.

The person who rents the hut must be up and back there the next day for the inspection and handing over the key.

All very well everyone bringing a plate of food but it should be organised otherwise you can end up with a very onesided menu e.g 50 salads and 3 desserts. Bowls and plates should be disposable or someone is going to have the job of storing and solving the puzzle of who's is who's.

It's been my experience for this kind of do, to keep things simple, less hassle, less cleaning and more time to enjoy the party.

It's all right saying everyone will "muck in" but people do leave early, get drunk or fall in love!

Often in a Gemienschaftcentrum the room needs some form of decor to create atmosphere, the old huts usually just have it.

This is just food for thought and not putting a downer on things. We may be a little late this year for this kind of organisation as many places are booked way ahead. If i can be of any help please pm me.
Oldhand.