I also enjoy my steak and kidney, but I'm not real good at making pies.
I usually start off with some Olive Oil, a little Worcestershire Sauce, some Oyster Sauce and some Fish Sauce dribbled into the pan. Add chopped garlic, sliced onion, chopped red capsicum, chopped celery, bacon pieces and sliced mushrooms and saute all. Then add the chopped, browned steak and kidney and cook on low heat to ensure tenderness before adding the flavouring.
Recently, instead of adding just normal Gravox or Oxo Cubes for gravy, I've actually tried adding a few available Finishing Sauces such as Steak Diane, Pepper Steak or White Wine and Mushrooms to enhance the flavour.
The taste has been great and, as soon as I can find out how to make pastry properly, I might even have a go at Steak and Kidney Pies !