I agree with downbytheriver about no shutters, just stick with your idea to beef up the white trim. And while I like the chartreuse door in the middle example above I know that's not everyone's taste. I think your red door would work if you do add a few more red accents, especially a few more red flowering plants, and maybe a red painted bench or Adirondack chairs on the lawn?

Thanks so much for your suggestions. Thanks for the photoshop, downbytheriver. Yes, I know what you mean about a gooseneck being low. I prefer the "up" curved style, too. I know the current trend is no shutters, but for houses like mine with no other architectural interest on the front, and small windows, they're left looking quite plain.

A red door would be a knock out!!
I am not a follower of the no shutter trend especially for cottage type homes like yours. However, your upper Windows can not accommodate shutters so it may not give a uniform look used only on lower windows.
Use a classic black lantern (large) for your garage door.
Add red in the landscape, flower pot on steps or some place else
Beautiful new roof.

the shutters need to be scaled so they look as tho they function, in size, so in your case they may actually look too big side by side. what about adding a roof line over your door instead?

Thanks for the ideas. I'd LOVE to add a pitched roof over the porch, and we may eventually, but it's just too much right now. The four front windows did have shutters, properly sized, but they were pretty beaten up, so they got recycled along with the aluminum siding from the back and sides of the house. My husband is framing out the front door as I write, so when he's finished, I'll post a picture. That might help.

This is what I was picturing for the lights on either side of the garage door, if the front door is red. I just thought an unexpected pop of color would be nice.

I did purchase these blackish barn lights, but can return them: