Depends on which ingredients might be considered rogue.
A lentil and mushroom pie might be excellent.
Lentil, mushroom and pineapple - not so much.
Now regarding the meat pie. The filling is the excuse to allow enjoyment of gravy-soaked pastry is it not ?
And such pastry with a morsel of filling is heaven ?
Most pies would be improved by halving the filling. Imho.