i think it should be based on POWER with atleast a gap of 2k is fair enough. but like also in my server its very hard to gain points coz u will encounter people who have lots of refine and lots of good ninjas coz their server is far too way ahead of others. i think this crossed server matsuri and arena are way unreasonable coz it will only gain the old servers not the new ones. im wondering if someone in the new servers still playing matsuri or arena LOL. im sure they will not win against old servers. so my suggestion is they should based ur opponents by power. im sure it will be a better gaming experience for all.