I dont know if someone else though about it but maybe in osu! mania the sudden death fonction of having full combo or fail could be changed to not pressing any useless key. It would become a mod that give more point ( or less lost if i understand how mods work for mania) because the sudden death for mania right now is not really usefull cause u can juste press 3-4 key at the same time to get a single beat.