Great! Oddly enough that exact solution didn’t work (5.2, Windows) but tweaking it just slightly did!
void SGraphPinSomeStruct::Construct(const FArguments& InArgs, UEdGraphPin* InGraphPinObj)
{
SGraphPin::Construct(SGraphPin::FArguments(), InGraphPinObj);
FSomeStruct DefaultValue;
DefaultValue.Str = "abcd";
DefaultValue.Int = 12;
if(GraphPinObj->DoesDefaultValueMatchAutogenerated())
{
GraphPinObj->GetSchema()->TrySetDefaultValue(*GraphPinObj, LexToString(DefaultValue));
}
}
Thanks again for the help! Learning this system has been a process, but quite fun in its own masochistic way.