1st thing is I don't know how you can install a set of liners and the valve seats still be concentric to the guide. When you do the seats whether it is stones or cutters that tooling always centers from the guide. Just a couple thousands off and they will leak air. And just from the photos the blending of the seats into the chamber will gain you 10cfm from my experience such as it is. And if the valve throat is not the proper diameter, then you also are leaving flow on the table. And while flow numbers are an indicator, I have found that using a bench that measures the speed of the air especially over the short turn is really helpful. While 28 inches is a standard, actual flow in the heads in a running engine is more like 60 inches. I can flow most heads to 35 inches with my bench and I usually crank it up at max lift just to see what happens. A short turn that has more than about 400 feet per second at 28 inches many times will actually loose flow if you flow them harder many times.