Something off the top of my head to consider
e.g. each player will be allocated points 1 for plat 2 for diamond 5 for masters. Each week a team can only submit a team with total points equal to say 10. This will mean you can have 1 masters, 1 diamond and 3 plats OR you can have 5 diamonds (obviously the exact number can be played around with). This way there is no point having too many masters, if anything it's more beneficial to have lots of diamond and plat players.
i can guarantee you that if something like this is enforced, a ton of players will be deliberately dropping leagues/avoiding promotion.
the winner of this league gets promoted to tier 3, that team should be the one most likely to do well in tier 3. league restriction rules would screw that up.
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i guess i need to learn how to play now...
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