I agree that players should be given a choice of games in the first round.
If we go with the three-round method I described, then I would recommend
letting players rank their preferences among the top 11 games, then do my
best to assign everyone his top four games in the first round. Assignment
of opponents would be based on who shares your top choices. As players
continued through the rounds, they would eventually have to play some of
their less preferred games. To retain some choice of games in the last
round, each pair of players would have the option of playing any game they
had both won against other players in the tournament. This option could
even be given during the second round.

Before the tournament begins, I plan to make Game Courier keep track of
how much time each player has taken. This could be done by creating a
timestamp list that parallels the movelist. I could also create a
timelimit function that causes a player to automatically lose when his
time runs out. So that all games in the tournament could be manually
checked to see whether the timelimit function was being used, I would also
include information on its use in View move. As for the timelimit itself,
how about 30 days per player. If both players kept an even pace, this
would allow a game to last as long as 60 days. Then, each round would be
given two months to finish. If everyone happened to finish the round
sooner, then the next round could begin sooner. With three rounds, the
tournament would last up to six months but could take less time.

I think four games at once may be doable. Game Courier makes it easy to
play multiple games at once, but most people will be playing in their
spare time, and they shouldn't be too overloaded with games. Playing four
games at once, most people may be able to manage a pace of two moves a day
in each game.