You can post suggestions/requests regarding Mannequin here, or as a new topic if you feel the need for it.
Request for components is also open (i.e. 'please add a maid costume') as long as it doesn't make me breach any copyrights (i.e. 'please add X character costume from game Y').
P.S. You might be interested in our Public Trello Board, where we keep track of our development status and targets.