Combine chicken broth and saffron in a medium saucepan. Bring to a simmer and keep it warm over low heat. Do not boil.
Rise and pat dry the shrimp with a paper towel. Season with salt and pepper to taste. Set aside.
In a large paella pan, or a very large skillet, heat 2 tablespoons of oil over medium heat. Add chorizo to the skillet, sauté for 3 minutes, stirring occasionally. Remove from skillet and set aside.
Add chicken to the skillet and cook for 5 minutes, or until browned and cooked. Season with salt and pepper to taste. Add onion and red pepper; cook for 5 minutes, stirring occasionally. Add garlic; cook 1 minute. Add rice; cook for 2 minutes, stirring constantly. Stir in hot chicken broth, cooked chorizo, tomatoes, lemon juice, paprika, 2 tablespoons olive oil, and parsley; mix to combine. Reduce heat to medium-low and bring to simmer; cook, for 10 minutes, or until the rice has absorbed most of the broth and almost tender.
Arrange shrimp over the rice. Scatter snap peas over. Reduce heat to low, cover with foil or lid, and cook for 5 - 10 minutes, or until peas are crisp-tender, and rice is tender. Remove from heat and let stand, covered, for 10 minutes.
Serve with lemon wedges and more chopped parsley, if desired.