Im positive arena is already cross server, the only thing for ranked is that u will only queue up vs people who are close to your power ( so like maybe 4k power difference) . Thats mostly why queue's are long and also those who are at the top havve no reason to queue because they dont want to lose their ranks. I think queuing vs people your power lvl isnt the right approach especailyl that arena is everyone is at lvl 100. It should be the same system it had before but with ranks because even my alt could beat higher lvl players or more powerfull depending on what team people ran.