There are several simple ways to increase flavour to tomatoes; add a pinch of sugar or a grated carrot when cooking tomatoes. Keep the seeds in the dish! Those little tomato seeds and ‘jelly’ trigger a lot of extra flavour, so cook a bit more rustic and keep the tomato seeds in the dish.
Less juice is lost in the tomato when they are sliced the ‘French’ way which is from stem to blossom (vertically)
Store tomatoes at room temperature. Tomatoes will not ripen any further in the refrigerator and actually, refrigeration can make them tasteless and turn the flesh to a mealy mush.
Want to extend the life of the tomatoes sitting on your kitchen counter? Place the stem-end down. This minimizes the air entering and moisture exiting making the life of the tomato longer.