I have some problems to navigate through my scene. What I miss is a simple mouse based walk through. Advantage - simple navigation with turns. Could it be possible to use the mouse as pointer the scroll wheel as back&forward move and the eyehight stay fixed (could be adjusted by Q/E). Click and hold could allow to change the view direction (like current, but in walk mode). It's not so different to the current control. Most important is the keept walk mode.