My ideas on this subject will be a bit different. I like the idea of FT pistons, with a enhanced, transfer area. Flow bench the transfer area to see what flows the best.
What I learned about fluid dynamics, say that the pressure will be equal, within any given space and that pressure will exerted by the square inch area, regardless of shape.
Flame travel is very different from pressure and I agree with moving the spark plug. I would put it on the edge of the transfer, angled to the cylinder. It's my understanding that Ford put it near the exhaust valve, to keep it clean but, with modern extended plugs, I don't think it's relevant now.
As for the valves and getting flow, since there is virtually no flow over the valve, you need to work with the curtain. Larger valves, have larger curtains so, I would install the largest valves possible at a 85% ratio and work the contour around them on a flow bench. Everything needs to be as tight as possible in the chamber but, give the transfer and the area around the valves, everything they need. i.e. min piston to head and min head gasket shape and min clearance for the valve head, to back of the chamber, to promote forward flow.
I would also use as large a radius as the top ring to top of the piston will allow, to gain flow in the transfer area.