Some quick thoughts from behind my work computer:
1)
Most important IMO would be the 2p vs 3p debate (I would say definately no 4p, and byes for the 1 or 2 players who can't compete because of rounding-to-3-issues). This directly influences issues like
venue (more room is needed for 2p tournaments),
duration (2p games last much shorter),
pairing system (Swiss only works for 2p, so you can use standard software for the pairings; 3p will problably have to be done manually, taking up time between rounds) and
material (3p games need less material, but still more than organisers can round up without help from participants)
2)
A multy-day tournament sounds like a no-go to me, because of scheduling issues, venue cost, etc, but I'm not against it, personally.
3)
Ruud, I'd be happy to run you through the swiss pairing system someday, but for a quick overview I recommend the wikipedia page.
4)
Has a 'bring your own kingdom' like approach been tried before? Or something like that? It would really help with the material issue. Kind of like decks players bring with them to certain Magic tournaments.
More later, but feel free to shoot at my thoughts
Steven