for a competition for all grades, attention will be given to less time will be required, e.g. 2005 and 2006 Singapore Open, but the system not fully tested for at least 3 years and dropped.
in chinese, for a team event, we could consider the sequence of upper horse, middle horse and lower horse, but for an individual event, to have 3 different groups before the competition started should be a fair and better system.
Duration and funding are the two main factors in addition to the more critical factor of manpower needed.
For ideal situation, we should have the method like Divisions A, B, C & D etc and to cater for promotion and demotion each year.
Within Bishan Club, we used round robin system before 2006 for up to 16 players, and managed to introduce the Division system in 2006 and 2007 due to less number of players (24 in 2006 and 20 in 2007) and the player(s) could be promoted to Division A or demoted to Division D within the same year, the concept is same as round robin system but less number of rounds for most of the players by using division system.
With bigger number of players, more years may be needed for promotion and demotion.