You could plant some taller trees behind the driveway that in time will frame the house on that side, then some redbuds or dogwoods in the front of the garage. Since your property line looks to be 15-20 feet on the other side you might want to stick some larger trees along the line but behind the house. Whatever you like maybe a Crimson King might go well with the shutters.

Here is a link that might be useful: Propagating Perennials

Thank you. What about the front of the house?? It's so naked, despite the fact that there is an island with plants and two trees. It just looks so void...

Your existing maples are very close together--they will become quite large trees. Also, when you plan other trees, keep in mind that it is nearly impossible to grow anything under maples--the fibrous roots suck nutrients and water out of the soil. Find out what other trees do well in your zone and look for some with deeper root systems--oaks are usually good.

The formality of the two trees together in a matching pair does not go with the style of the house. You have a fairly big place, maybe you should hire someone to draw up a plan.

Thank you for your input. I suspected that those maples were too close too. I just moved some of the shrubs that were planted in front of the house, because they will be humongous. I don't know why those people who built new subdivisions never consider the mature sizes of trees or shrubs, as well as planting trees too close.

Is it going to be ok if I move those maples now? When I moved those shrubs, I broke some of the roots. I only have a shovel.

Your trees are probably leafed out now in your zone. Plan to move them in the fall after the leaves drop. Get someone to help you and dig the biggest root ball you can handle. Water well through the winter if it's dry, and through the following season.