I love the idea of a yellow front door. Could be a beginning.

They are from Houzz

Well, so many possibilities. Navy blue shutters & yellow front door. The garage door same color as siding or trim around windows.

How about remove the shutters completely? A buttermilk yellow would work nicely or even a teal. The garage door should be a neutral earthy color.

I would paint the garage door the same color as the tan siding. Shutters paint black and leave the door red. (I love a red door; very welcoming).

I told my husband about the shutters not fitting, and he wants to take them down "on principal." lol.

The shutters are not the right size. I’d remove them and do some landscaping. Paint the front door one of your favorite colors to complement the brick.

The shutters should always be sized so that they could cover the window if closed. Yours will never do that because of the double window on the left. If you have budget to make the shutters wider I would do so, knowing they will still not be properly sized. Wider shutters would just be more prominent and the house needs them for interest. I would paint them a classic glossy dark green/black. I might paint the garage the same and I would use a much stronger red on the front door. These colors would play up the classic appearance of the house. For further curb appeal I might add a classic column to replace the post under the portico by the front door. Then I'd start the landscaping!

I really think for the most part the sizing of shutters is a personal preference. They are used decoratively now so they can vary in size. For your windows I wouldn't really bother to change them.