there are no public plans on any new game mode atm, but you can always support new game mode requests in the feature request forum, this one for example t/19307
it seems a lot like osu!mania, so try to get used to that instead. also wrong forum to ask this.
Google brought me this (theowest was wondering what is Audition Online before editing his post):
If this is the game you are talking about, don't count on it at all. First, osu! has already a lot of modes and adding another one would be too much. Secondly, that is really not the type of mode osu! would propose (that's too hipster)
i would like to cordially advise all support team members and just about anyone else who feels they can make any sort of valid claim to the difficulty of implementing a specific feature: don't, because you have absolutely no idea how hard or easy anything is to code into osu!. if you did, you'd be a developer.