I dunno, maybe the read speed can be increased by tinkering with the firmware. There is firmware for some drives to remove the "riplock" but I don't know if it ever gives more than 16x reads.
My old Lite-Ons can have their read speed for various media be adjusted easily with omnipatcher. But omnipatcher doesn't work with new Lite-Ons, and the highest speed these old drives can be set to is 16x.
One thing I've learned is the faster the read speed, the noisier the drive. At least when a disk is first inserted and the drive is trying to figure out what's in there.