In a large skillet, cook sausage and onion over medium-high heat, stirring frequently until meat is thoroughly cooked and no longer pink. Stir in banana peppers and jalapeno peppers; cover and cook 1-1/2 minutes. Reduce heat to medium, stir in cream cheese and chopped tomato; cook uncovered until heated through (about 5 minutes). Fold in red pepper; add optional ingredients if desired. Serve warm in a chafing dish, with chips or crackers for dipping. Garnish with additional diced tomato and cilantro or green onion if desired.