If you want the easy version of it, Phase 2 and 3 are what is slowing down your extractor. Phase 1 and 4 have a minimum torque and require much less rad/S to reach almost instant speed than 2 and 3. Get a CVT unit, attach a redstone clock to it that periodicaly switches its modes. have it switch the input between 512Nm of torque and whatever speed that gives you and 1Nm of torque with insane speedsI understand how RoC works. I used the magnetostatic engines in my live world, but for testing I tried many different setups. In my tests I had jet engines, bedrock gearboxes, etc.. and even with huge "Power" (speed/torque) going into it, I didn't notice a difference. You said that you can make it faster with more "Power" (speed/torque) so I am going to try again when I start up again. Could have missed a step or it could have been a bug in that release on that day. Not a big deal.
(and it doesn't change that mekanism has better speeds/output with much less complexity.)