I usually use Romaine lettuce though red leaf or baby green mixes would work. Tossing some baby spinach in would be tasty too. I like the sturdiness of the Romaine with the cheese. It seems to hold on to the cheese and dressing better than something like red leaf. I also like to either tear or chop the lettuce into pretty small pieces so the end result is kind of like a chopped salad. (I didn't quite accomplish that in these pictures.)
I also added chopped cucumber and sliced radishes. I didn't have other veggies at the time but I love celery and tomatoes in a Greek salad.
I also didn't have any pepperoncinis but they are nice on the side with a Greek salad.
But the dressing! I make a basic vinaigrette dressing but I use kalamata olive oil and red wine vinegar. I also add plenty of lemon juice and a touch of sugar. I also add fresh ground pepper and crumbled dried mint. I love dried mint. Yum. Enjoy!