I like the shutters. Id get a new door either black or a bright color with matching colored large pots or urns with TOPIARIES flanking the entry. Also, add a small hedge "Minimalist Landscaping. On par with stripped-down details in Colonial homes, landscapes lack conspicuous ornamentation. Many rely on geometric combinations of shrubs and trees as a restrained softscape accent." Source: https://www.bhg.com/home-improvement/exteriors/curb-appeal/colonial-style-home-ideas/

here are some combos to consider. see if you like any of them Here's a peek at that type of metal roof I mentioned (you could also do this type of metal over those upper windows) This combo would look great w/your natural wood door. bring in some wood posts, trim, garage doors, or even some shake, just to further enhance the wood door. You have that large expanse of siding. what if you broke it up somewhere w/the same color in a composite shake, like shown here? see how the front part was divided with upper being shake? maybe add some stone or brick? another option is to do vertical board and batten to also break up all of the horizontal siding.

I do not like shutters with wide window groups, because they are obviously fake. I would remove them and paint the trim around the windows as well as on the corners of the house and the fascia at the edge of the roof. Below is a home with three exterior colors that accent the lines of the house. The contrast between light, medium and dark tones adds drama. The rest of your curb appeal can come from landscaping. Start by adding a concrete path from the front entry to the driveway. If you can't do a solid concrete walk buy the largest paving stones (usually 18"x18") and set them between the entry and the driveway. This will allow you to make a 36" wide path that is easy to walk on, and looks good. Here is one simple style. It looks like there is already a planting bed between the entry and the driveway. Fill it with plants that stay green through winter, but be careful to choose shrubs that stay small. Dwarf only means smaller than the species, so check the expected mature height before you buy. Be sure to place all plants far enough away from the house and walkways that they don't crowd. If a plant is expected to grow 4' wide, plant it 2' from the house or path. Fill in around them with perennials or annuals to cover bare ground and provide seasonal color. The bed on the side of the garage is narrow and therefore best suited to small upright plants such as phlox, veronica or daylily. If you want a shade tree make sure to avoid underground utilities when you dig. Don't plant a tree or any large shrub between the front door and the street. Don't create a mulch volcano around new trees. If your soil is heavy, deep mulch can lead to fungal disease at the base of the trunk. This applies to shrubs as well. Mulch is supposed to be temporary just to cover bare ground. You can let the lawn grow up to the tree.

I wouldn't say it is without any curb appeal. It is attractive with a kind of rustic vibe. I would not ditch the shutters. They are completely appropriate to this house. If you removed them, you would be left with even larger expanses of blank wall, out of balance with the window sizes. Although the shutters on the two short upper story windows could be a bit wider, some will repeat the dogma that they should be sized to look able to actually cover the windows when closed and should be removed if they don't. That is clearly impossible here and would also give an unbalanced feel. IMO of course. I might give the front and storm door a color that works with the siding and roof (pumpkin, maybe, or a warm strong blue or green). I can't really see the porch/front door light, but the ones by the garage door are rather undersized. So the front door one might be also. What is really needed is better landscaping. The rows of small/narrow shrubs don't add much appeal, and still won't once they've grown. I would consult with a garden center (if they have a designer on staff, many do) to come up with a more varied and naturalistic planting scheme.