There actually are a few such sects. Google “Abdul Palazzi” - he’s about the closest thing around to a Muslim Martin Luther.
Palazzi is an interesting one. He’s essentially a Muslim Zionist, and describes himself as one.
Frankly, the Ahmadiyyah Movement is nothing to get up-in-arms about. They are genuinely persecuted by Wahabbis, and they are pacifists, opposed to radicalism and extremism.
When the Ahmadiyyah or Sufis set up a mosque, it’s nothing to worry about. They tend to be a better class than their co-religionists. On the street I lived in Berlin, there was a Sufi Center downstairs. Really nice folks, actually, and from time to time, I’d go sit in and listen to the dhkir and watch the dervishes do their dervish thing, which was really cool. And good eats afterward!
If all Muslims were like the Ahmadiyyah and the Sufis, the Middle East (and the world) would be a far, far better place.