When planning a concert I believe that audience understanding and enjoyment has to come first. I put a lot of care into matching each programme or concert with the performers, instrumentation and venue. This often leads to combinations of players not usually heard together and to exciting new interpretations and collaborations.
I've experimented with creating listening guides - small folders for each audience member containing cards with easy to understand diagrams and beautiful artwork enhancing the 'storyline' of the programme. People love them, but they're a lot of work to make! These days I find just couple of interesting comments by the performers between pieces is all that's needed.
More than orchestral music, I find chamber music really draws the performers and the audience together in a mutual experience of the music. Every performance is different yet special!