Aperiodic multilayer interference coatings are of particular interest for a variety of hard x-ray applications, including target diagnostics, astrophysics, high energy physics and free-electron lasers. Such applications require large field of view along with the highest achievable photon efficiency for their optical components, pushing reflective multilayer coatings to their limits. This work investigates the design, experimental performance, modeling and optimization of high-reflectance aperiodic multilayers. Multilayer design starts with the implementation of an analytical method developed in the literature, which calculates the most efficient coating, featuring the highest achievable reflectivity with the least number of layers. A numerical optimization step is added for smoothing of high-frequency "ripples" or to comply with any specific requirement in terms of spectral or angular response. The design process also includes material-dependent specificities (e.g. typical roughness, interlayer formation) which are often crucial for accurate prediction of actual coating performance. We applied this method to develop novel high-reflectance broadband multilayers at 17.4 keV (Mo Kα emission line), working at angles of grazing incidence up to 0.6 degrees. The design methods employed in this work are presented, as well as the results obtained for a few multilayer systems, including Mo/Si, W/Si and W/SiC.