I would probably stick to the family of colors you have now. I would paint the floor a darker putty color , darker than the house color, which is earthy and would make the floor less noticeable. Since you have Cranberry and black iron on the house already I would go a couple shades darker on the door, maybe a black cherry. This would be a simple but classy color scheme that would blend all the colors. Your house should look great with landscaping since red and green are complimentary colors and each will make the other look richer. If you want other colors I would stay in the color family for example the door could be black or the same as the shutters. Consistent colors work better on a large scale like a house. Good luck and enjoy, and after all it’s just paint if you don’t like it repaint.