73 Dart Sport Reanimation

Valve diameter isn't as important as "curtain area", which is valve circumference X valve lift. In reality, the combustion chamber & cylinder walls will shroud part of the curtain area, so figure about 90% effective curtain area. I try to keep velocity fairly consistent; start at the manifold, slight taper back to the choke point (the valve guide area), then spend considerable time blending around the seats.

Most heads flow 95% of potential around the manifold openings, 75% at the choke point, and only around 55% past the seats. Keeping that in mind while porting, most folks spend most of their porting efforts where they get the least gains (port matching).

Looking at your pictures, the only thing I would definitely flag is the sharp edges around the valves in the combustion chamber. I'd use a sanding roll to flatten & radius them. Sharp edges in the combustion chamber promotes detonation.