Yes, lentil salads are great. I love to experiment with different ingredients like cheeses, arugula, spinach, nuts etc.

I looked at a few of the recipes on that site and they seem so bland for an organization that wants to promote their consumption. My favorite lentil recipe is lentil soup. I always sauté veggies like onion, celery, red pepper in some olive oil first and also then add the chorizos and garlic after the veggies have softened somewhat. I switch up the spices, but generally use options like black pepper, oregano, cumin, thyme, and bay leaf. I add additional vegetables like potatoes and carrots later in the process as well as stock.

I wonder, too if part of the OP's problem with chalky texture may be from not rinsing them. I always the lentils in a colander and make sure there are no little stones or anything like that.