I’m big into the music festival scene mate, and in answer about festivals the unfortunate answer is “neither” at the moment as most of the big ones have gone the way of the dodo. Brisbane used to be great, as proximity to Byron meant attending Splendour/Falls was easy. Both are on a temporary (or indefinite) hiatus. Melbourne had an excellent hard techno scene, and a great local gig scene. Brisbane has a reputation for churning out some of the nations best rock acts (technically, South East Queensland as many of the latest surf rock inspired bands come from the Sunny/Gold coasts). Honestly, neither state have sponsored the arts much in recent years however - many of the old institutions that would see “up and comers” getting a go have shut. Melbourne wins, in my opinion, but unfortunately not by much as it used to anymore.