I've a few suggestions for you.
I used to always make 'hot salads', and sautee veggies in a nice sauce, and eat it over greens. It would slightly wilt them, and it tasted really good! I experiemented with many different sauces - basically, anything you like! My favourite combination was sauted veggies like eggplant, bell peppers, mushrooms, cherry tomatoes, and so forth, with fresh italian herbs, and pureed raspberries as the dressing.
Another suggestion would be to steam them, in general, with spices. It just will taste like spinach.
When I make soups and stews, I add any greens I have in the fridge, basically, other than iceberg (which isn't ever in there, anyway)... But basically, anything will taste fine.
What 'tastes' do you like for your dressings? Do you like dijon, or spicy, or sweet, or curried type things? what about a warm Caesar?