I think sewing is outside of my DIY abilities. Besides, adding a clear panel to the top of my Nova 5 would be counter-productive, at best.
The more I think about it, it also seems counter-intuitive to secure a velcroed flap over your gear for indoor taping. If the meters show rec levels need adjustment, I am going to have to rip open the velcro to get at the controls, and this would be audible in many circumstances. Maybe I just need to get one in my hands to see how they work.