I love green smoothies too- I wish my blender were as easy to clean as my aunt's Vitamix. I usually do:
2 bunches one leafy green (like spinach or bibb lettuce)
1 bunch different leafy green (like romaine or kale)
2 big leaves collard or swiss chard
1/2 bunch cilantro, basil or parsley
2 cups orange juice
2 tablespoons coconut oil
It's pretty high in sugar and fat, but also in fiber and vitamins and it makes me feel amazing and treats my poor digestive system really well. I usually do a ratio of one banana to one tablespoon coconut oil. The coconut oil makes it really awesome! I made some horrific smoothie mistakes before hitting on this recipe. Next thing I want to try is nuts in my smoothies- I definitely need to soak them first, I hate little hard bits in my food.
I've tried berries and stuff, and it just hasn't made a big difference in the flavor or texture(except seeds. see hating little hard bits!) I'd include them for nutrition but my base recipe is pretty good the way it is. On the other hand, I can and will put ANY veggie into this recipe, including celery, carrots, avocado(watch out for drinking guacamole!), cooked rutabaga and cauliflower, apples and pears and raw ginger... it all depends on my mood.