With a POD in or after 1900? Man, that's going to be incredibly difficult. But let's give it a try anyway. And for starters, as a potential POD, how about having the Afghan-backed
Basmachi movement garner more official support from Afghanistan? Instead of merely supplying them with arms and offering them refuge for a brief period, as they did IOTL (due largely to the murder of King Habibullah Kalakani, their most vocal and enthusiastic ally, after only 9 months on the throne throwing a spanner in the works), the Afghans send their own military forces across the border to intervene in this conflict directly (with the approval and financing of this effort by the British from behind the scenes) after the October Revolution and the fall of the Russian Empire to the Soviets. This results in the Afghans eventually emerging victorious against the Tashkent Soviet and the newborn Red Army, and securing the independence of the majority of formerly Russian Turkestan, along with the Emirate of Bukhara and Khanate of Khiva, under the Afghans' military leadership by the mid-20's?
Then, when the
Kumul Rebellion kicks off in the early 30's ITTL, the Afghans intervene here as well, just as they did IOTL, but through direct military action here as well; they're the first to officially recognize the First East Turkestan Republic as an independent nation, and after Turkestan, Bukhara and Khiva follow suit, they manage to persuade the British, Iranians and Turks to give East Turkestan official recognition as well. As such, the Kumul Rebellion is also successful, also courtesy of the Afghans, with East Turkestan (better known as Xinjiang today) also joining Afghanistan's own established regional military alliance. And thus, by the early 1930's, King Habibullah's Afghanistan has become the undisputed 'Great Power' of Central Asia. Along with the Afghan 'mujahideen' having come into existence a full fifty years earlier ITTL than IOTL, with the Soviets as their deadly adversaries, and the Western World as their greatest allies on the world stage. How would things pan out in the end? No idea. But wouldn't it be fun to see how they did?