Cook bacon in large saucepan, or dutch oven, until crisp, stirring occasionally. Remove bacon from pot with slotted spoon and drain on paper towels. Drain off bacon grease, reserving 1 tablespoon drippings in pan.
Add chopped onion, celery and carrot to pan and saute, stirring as needed, until crisp tender, about 12 minutes. Add broth and potatoes; bring to boil; simmer 12-15 min until potatoes are tender.
Add cream cheese to soup, cooking and stirring until cheese is melted. Stir in milk, fish, shrimp, bacon and seasonings. Bring soup to boil and cook, stirring frequently 3-4 minutes until fish flakes easily with fork.
At this point I remove pot from heat and stir in shredded cheese, reserving a bit of cheese for garnish. Stir until cheese has melted and thickened soup a bit, then add salt and pepper to taste. Be sure to taste before salting as the bacon and cheeses add saltiness.
Ladle into bowls and garnish with reserved cheese as desired.