Carbide cutters work great in getting the basic shape then I used the porting kit (sanding rolls. They last much longer than grinding stones) that Summit sells for smoothing things down after I get the basic shape ground in. I also run the air at 60-65 psi to slow down the die grinder so not to take too much out with the carbide cutters then. 90 psi is ok with the sanding rolls. Yours are looking ok so far. Open up the area beneath the valve seat area too. Got quite a big lip there giving a funnel effect. I did my EQ's and found quite a bit in working the intakes even in spite of the huge pinch they have right at the port entry but the exhaust didn't improve a lot even though I took mine down to look very similar to 2nd pic you have there.
Oh yeah, use the shortest carbide cutter you can as the longer they get the harder they are to keep stable. It takes a long cutter to reach in through the port window but doing a bowl doesn't. That's been my experience with them.
