You can make the cream cheese mixture up to 2 days ahead.
Pulse first 3 ingredients in a food processor until smooth. Add olives and next 3 ingredients; process until finely chopped.
Spread 1 Tbsp. cream cheese mixture onto each bread slice. Top with sliced grape tomatoes and hard-cooked eggs, or basil leaves, celery, and radishes, pressing lightly. Trim crusts from bread. Cut each bread slice into 4 squares or 2 rectangles.
