When assembling the salad, slice each variety of tomato in a different way. Slice the Heirlooms into circles, the Cherries into halves, and the Early Girls in wedges to get a range of textures. Together, they create an interesting contrast of shapes, showing off the character of each variety.
This is not a super technical recipe. The amounts vary depending on the size of the plate or platter you are working with and your personal preference. I like to go really light on the vinegar so you can taste the natural flavor of the tomatoes.
Slice the tomatoes and arrange on your platter, sprinkle with sea salt. Next, add the olives and onions with a splash of sherry vinegar and a drizzle of olive oil. Finish with a little pepper and serve.