You can enable "constant velocity" in settings
Its not as easy as it sounds. Auto-thrusting may be called
auto only when it can thrust more than once. As result, maintaining penetration is crucial and I cannot maintain it at higher speeds. You may notice that whatever speed you choose, pull-out always decelerates, and it is most noticeable at max speed. There is no way to precisely move hips or detect actual penetration depth.
On my potato, at 40-50 fps, at highest speed single motion takes 6-9 frames. With all lags, my math cannot predict safe hips position. This stuff must be made by someone who understands how holes and penetration works, I do not posses this knowledge.
I
told earlier that I'll add some tweaks to increase speed, but I do not have any idea when that update will occur. Right now I have very little interest in playing SMA or modding it.