A sheet of graphene a few layers thick is much more transparent...

A sheet of graphene a few layers thick is much more transparent than silicon based glass. There is potential to coat window glass in graphene and develop a multitude of uses for it, including solar thermal storage and home insulation.
Most of the commercial uses for graphene are still in development, many are just theoretical and some haven’t even been thought of yet! The initial sales of FGR graphene will go towards increasing product durability in a number of industries because there is evidence to support this property already. Graphene can be used in the shoes you wear and the pavement you walk on. Perhaps it will be in the car you drive and the plane you fly in?
Graphene is potentially one of the most versatile materials we have, all IMO of course. I encourage you to DYOR to see the research taking place all around the world.