Limiting yourself to Va for normal steep turns in a light aircraft probably is a bit conservative.
The current rules for load design are at
FAR 23.333 (and the envelope picture is a bit easier to read in
this download) while the required positive load factor is given at
FAR 23.337.
Given that the typical light aircraft has trouble maintaining a level turn at bank in excess of 60 degrees, I think that the risk of a structural overload probably is not great ....