When you are searching for a designer, search for one that is local to the area where you want your home built. Typically, local designers will have a better knowledge of the region, the laws, and the other issues surrounding your new house building project.
There was a time, quite recently in fact, when the most important attributes of buildings were their aesthetic qualities, fitness for the intended purpose, and structural integrity. However sustainability objectives - paying closer attention to the soundness of the architecture from the perspective of the environment - are quickly becoming the overriding factors in contemporary home plans.
Nowadays architectural soundness has acquired a new meaning, with the advent of sustainable designing. A dwelling sheathed in solar panels has a very different aesthetic than the usual suburban house. Multi-unit housing which eliminates the thermal bridges created by extensive glazing and concrete decks do not share the aesthetic of glass paneled high rise towers. Passive solar designs often borrow elements from local architectural styles to address local climactic conditions.
Given their professional experience in house designing, it can be helpful to hear why certain elements will and will not work as you may envision. Your architect will be able to show you 3D walk through plans too. This can be useful exercise to examine sun patterns at different times of day and get a feel for the scale of your future modern home.