Light tahini works well in salad dressings, IMO. This recipe for Smashed Cucumbers with Cumin Tahini has a very nice balance of lime or lemon, vinegar, oil, sesame, cumin, and garlic; the optional chili vinegar that goes with it is also a delight. (I generally am too lazy to bother with smashing the cucumbers, unless the news has been particularly vexing.) That same dressing has become a dip for other vegetables, a dip for cooked chicken, a dip for celery....hmm, maybe I'll add some to my next chicken salad.
I had never heard of celtuce before. I'll have to see whether our specialty markets carry it.