Hi Charlie, don't know anything about your setup so might be way off here.
If you are using a Single nema23 with 70v to drive 2 x 10mm pitch screws then you're doing well to get 10M/min. Or if you're using single Nema34 with only 70V you still won't get much more than 10Mtr/min. You'll need more Volts for Nema34 to get higher rpm.

Now 2 x 23 will get you little more speed but my question would be WHY.? You can't cut many materials higher than 10mtr/min, woods etc will be much lower feeds and the machine isn't massive so 10mtr/min rapids will still get you end to end quick enough.