I think salads got better for me when I realized lettuces wasn't the base requirement. I've built a lot of salads with cucumbers and tomatoes as a base. I also roast veggies like jiffypop. Oh, and I do like using the broccoli slaw mix. It's a lot crunchier and feels very filling.
I highly recommend the popular raw kale salad made with Tuscan kale (Cavalo Nero, black kale) Recipes abound on the internet. I go with the lemon juice, olive oil, garlic, and parmesan blend version. Just enough oil to lightly coat leaves and bring it together. Keeps in the fridge for several days.
Helpful tip: I buy spinach and mixed greens in large tubs from a warehouse club. But sometimes don't get all of it eaten before it goes "south". If you put a paper towel across the top of the greens and "hang it out" the lid, it wicks moisture from the greens. Weird, but it works! I have had spinach last a week longer than the expiration date.