would use ATP rankings model https://www.atptour.com/en/rankings/rankings-faq
1) the rankings period is the immediate past 52 weeks
2) best from 10 national games( base point 15), 20 state games (base point 10), 40 city games(base point 5)
3) each game points, (game level point + self score-opponent score)*(last week opponent team rank score/last week self team rank score)
should make a wordpress plug-in
1) player add/modify/inactive
2) permission, who can enter
3) add/modify/void games, nation/state/city level, pick players, enter date, duration, scores.
4) display result, players, ranking, scores, total games, win ratio
5) play detail, alias, game detail. current rank score, last week rank score