I think one or two thematic Tournaments should be enough for a start. If
one, I would prefer Chess/Xiangqi/Shogi. If two, I would suggest an
Oriental Tournament and an Occidental Tournament, something like
Chess/Grand Chess/Fischer Random Chess (/Capablanca Chess?/ Berolina
Chess?/ Extinction Chess?/ Cylindrical Chess?). Or maybe an Oriental
Tournament one year and an Occidental Tournament the next one.
For the main Tournament, I would suggest to give 90 days to each player
and to begin all games simultaneously, even without a move-veryfing
preset.
And if there are too many players for everybody to meet everybody, I would
suggest to qualify the seven higher-ranked players of a round-robin into a
six-game final.
Computer help is illegal, of course, but I think we should state clearly
whether book help or Internet help (particularly for Chess opening theory)
is allowed once the games have started.