Redoing kitchen sink trap/drain?

Is there anything I can do to reconfigure the drain pipes and trap under our kitchen sink to make better use of the space? It has connections for both a dishwasher and washing machine drain, but we only need the dishwasher.

The entire cupboard will likely be replaced as it appears to have suffered a leak previously. This will take some thinking about. I think I'll do a large cut out to the back right corner and box in as I can't really disconnect and reconnect the pipes! I'll need to make the stopcock accessible too.