My MIL makes a ginormous bowl of greens every Sunday. I think she adds shredded carrot, celery & possibly peppers to her mix of greens.
In individual containers, she preps wetter veggies like cucumbers, mushrooms, tomatoes, olives, etc. Every night, she sets everything out and people can make their own salads. When an ingredient is out, it's out for the rest of the week.