What I know about salads I owe to une femme who took me in as a boarder in Toulouse. Despite falling on hard times, she presented a balanced meal every night.
The structure was usually entrée, a simple main course (one night, when we had guests from the country, it was roast pheasant, pick-out-the-buckshot-as-you-eat, with sautéed apples; one of the best meals I've eaten), then salad, then fruit.
The salad was a mix of soil-grown leaves, bought at the bi-weekly market. My favourite was heart of cos, treviso and rocket, dressed with vinaigrette: a teaspoon of Dijon mustard, salt and pepper, red wine vinegar and olive oil.
La femme would clean and dry the leaves, place them in a bowl, make the vinaigrette, then pour it down the side of the bowl. After the main course, the salad was tossed and served - a habit I still observe when hosting dinner parties.
I like my salads bitter with a classic vinaigrette: rainbow chard, chicory, kale, dandelion and fennel fronds, snow pea shoots and sprouted mustard. Salad in the French meal is a palate cleanser, a pause - punctuation at its best.