My dad(retired) enjoys working in the garage everyday. He spent considerable time cutting my valve seats. The seats were a bit deep, so we went old-school, and cut down some shovelhead intake valves(which are larger) in the lathe and relocated the valve seat farther out. It works . . . sometimes. Other times it's best just to machine out the old bronze seats, and press in new steel seats.
These late-model valves have an improved shape too which should help flow. I'm thinking maybe an Andrews AB grind camshaft? Mild with a slight boost where I want it . . .