Personally I think that looks pretty good. There's no templates, no inheritance. Not sure what would make bloat there nor latency. Whatever the faults of the syntax for folding, it's got to be better than VA_ARGS hasn't it?
This is not valid C++14 however, so it doesn't compile. If you replace these, you'll probably still get a stack overflow while expanding the templates because there are almost 7000 arguments to a single function call.
I was referring to the use of generic functions (ie. with an argument with type-specifier auto) which is not C++14. Your copy of g++ may accept it as an extension.