This is what Ken writes about how many players you need:
two or three players with up to four characters a piece is ideal. When it is necessary for a GM to try to cope with more than three players, it may be necessary to limit the number of characters they can use at one timeFrom my perspective it's kind of amusing that the idea to start with one character per player and add characters if you're short of players, seem to be far from Ken's experience. Apparently the norm was to have more than one character!
David writes a very interesting article about how to have one PC as your main guy, and then a Loyal Follower to take over when the big guy dies. It's a neat and workable way to have a bigger choice of what to play, but also to keep continuity when some calamity strikes the party.
I have been talking about troupe style play before, and it struck me as kind of amusing that when that idea was introduced with Ars Magica, that style of play was already way old. The new way was the old way. Nobody knew Ars Magica was that "old school", right?
When I ran my Dungeon of Voorand campaign, I used the "stable" approach with three characters per player. That was my attempt to play it like I'd read they did in Phoenix when the game was invented.
So, if you want to play your game the way they did it "back then". Break out Ars Magica, or read that article in Fight On! Or roll up a stable and play T&T. The more the merrier. I guess they knew it already during the seventies.