Personally I'd agree. If you want to add a third color I'd do it on a smaller scale somewhere other than window trim... Just my $.02

I don't see the after pic. But would love to see your progress.

If you are selling now, just give a quick coat of the same dark green semi-gloss or satin paint to the shutters and trim. Put your money into neatening up the landscaping and adding some bright flowers from gallon cans the week it goes up for sale. Remove the dangling pot, too.

I would keep the posts white. There are so many of them and yet they don't frame anything per se. I think a gray almost what you have but a bit less blue is a classic look for the porch deck. Paint the ceiling haint blue. This deck is a bit too light. I think the window trim would look good in a light beige. Lap siding in white.