Staggered ribs will give you less steering than minispikes. They are easier and safer to drive on but ultimately maybe a little slower on a lap.
You need to be on yellow minispikes for astro with some medium inserts. All astro is different, some astro tracks dictate worn spikes to be the easiest to drive on whereas others you need the edges to be on the spikes for ultimate grip.
Start with a new set of yellow minispikes ( from rc lazy of course
), cut the inner and outer row off the fronts and the outer row off the rears if you are finding that the car is grip rolling i the bends. TBH, i dont recall racing on any astro dry track where you dont cut the outer and inner off the fronts at least. I suspect that you may not be getting full lock if you are getting a lot of understeer. turn the car on, turn the steering all the way to the left with the transmitter and hold it there, see if you can move either front wheel left or right against the servo. If you can you need to adjust the end points on your tranny and/or check the geometry. Repeat for the right lock.
HTH