As a general rule, the best holographic experiences are those where an end user can be completely immersed and forget the fact they are working with augmented reality at all. As a general rule holographic models should not be larger than the physical space you are viewing them in. Working with very large models can reduce immersion by creating screen door effects from the limited HoloLens field of view and introducing depth flattening due to the limited stereo differences between objects rendered at a great distance from the display. If the goal is to design an immersive experience of a large scale model (e.g. a model that is larger than the physical space you are currently in) it may be a better application for virtual reality.