Is there a secret to flavouring with herbs
If you're adding inordinate amounts of herbs with no effect, then that sounds to me like a problem with the herbs themselves.  If you're using dried herbs, they could just be too old.

To me, dried basil and oregano and marjoram just never taste like much. Fresh, however, they're quite strong. Tarragon, chervil, and dill, on the other hand, do "work" in dried form, and in fact you have to be careful with tarragon. I guess I'd put rosemary in that category too but thanks to some out-of-control plants I've got more fresh rosemary than I could ever possibly use cooking for an army.