I don't want to get sideways with anyone, and ultimately what we do to protect ourselves and our family is our own business...
However, I would not recommend using hornet/wasp/bug spray as a non-lethal force alternative. Pepper spray is used by law enforcement, and is essentially safe on humans while being very incapacitating. The potential for long lasting or permanent effects are slim. Government agencies set the standard that pepper spray is a viable method of employing less than lethal force.
Bug spray is not tested on humans, and not recommended by anyone of authority or expertise for use on humans. This would be the ultimate "off label" use--since spraying on a person is directly contrary to all warnings on the can. There is definitley a potential (I would think) for blindness or other types of permanent damage or even death. Not to mention, it's just not designed to work on humans, so I question the effectiveness of "stopping" a threat.
We may not, in the heat of the moment, care what damage we do to someone intent on doing us harm--but there are definite liability problems with this idea. God forbid a jury thinks you were wrong to use this level of force and you blind someone in their prime working years with a family to support. You can't dishcarge that liability in bankruptcy, and you could be haunted for 30 years with a potential multi-millon dollar judgment.
I also wonder whether wasp spray might be considered lethal force as opposed to non-lethal? I think it very well might be. If so, you would be much better off using a gun if lethal force is justified.
My two cents: don't even consider using wasp spray on people.