Having lived in Southern Spain for a long time I make Gazpacho quite a lot in the Summer - it does tend to be more pink than red when the tomatoes are skinned and de-seeded and the bread added.
Tomato juice is fine to add to it if there is not enough liquid from the tomatoes - imo.
Another great soup from down here is Sopa de Ajo Blanco - which is Almond and Garlic soup, again served cold, which is very tasty. We are lucky enough to get the almonds from our trees. Lots of recipes on the net - try the one from Delia Smith.