Allow easy interchange between open score and closed score choral writing

It would be rather useful to be able to view some parts of a choir score as "closed" and other parts as "open". For example, for printing, I would prefer closed score to save pages. However, for score editing, creating each part separately, or playing each part, I would prefer open score. As the question asked, it would be nice to be able to do this "view" change at libitum for different parts of the score (such as, homophonic parts or polyphonic parts). In order to be able to achieve this, there could be just as many different staves (for different "instruments" or human voice parts) as are needed, but ability to change "view" option, for example, to magically transform the open score to closed one, from part to part, would be convenient, and vice versa. On that topic, for choir scores, such as orchestration reduced to piano or organ accompaniment, many instruments may appear on the piano/organ stave. If this can be done by placing different instruments on different underlying staves but by making them appear as a combined accompaniment stave, that would be very useful, too. It is a bit like showing different stave together as overlay of different "voices". However, "voices" can't be combined to one save or separated easily to multiple staves easily. Maybe a bit different combining/separating mechanism are needed?